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If you edit using a mobile connection, try using a Wi-Fi connection, and vice versa. If you are using a corporate internet connection, switch to a different Wi-Fi network. If you have a Wikipedia account, please log in. </p><p>If you do not have any other way to edit Wikipedia, you will need to <a href="/wiki/Wikipedia:IP_block_exemption#Requesting_and_granting_exemption" title="Wikipedia:IP block exemption">request an IP block exemption</a>. </p> <style data-mw-deduplicate="TemplateStyles:r1214851843">.mw-parser-output .hidden-begin{box-sizing:border-box;width:100%;padding:5px;border:none;font-size:95%}.mw-parser-output .hidden-title{font-weight:bold;line-height:1.6;text-align:left}.mw-parser-output .hidden-content{text-align:left}@media all and (max-width:500px){.mw-parser-output .hidden-begin{width:auto!important;clear:none!important;float:none!important}}</style><div class="hidden-begin mw-collapsible mw-collapsed" style=""><div class="hidden-title skin-nightmode-reset-color" style="text-align:center;">How to appeal if you are confident that your connection does not use a colocation provider's IP address:</div><div class="hidden-content mw-collapsible-content" style=""> If you are confident that you are not using a web host, you may <a href="/wiki/Wikipedia:Appealing_a_block" title="Wikipedia:Appealing a block">appeal this block</a> by adding the following text on your <a href="/wiki/Help:Talk_pages" title="Help:Talk pages">talk page</a>: <code>{{<a href="/wiki/Template:Unblock" title="Template:Unblock">unblock</a>|reason=Caught by a colocation web host block but this host or IP is not a web host. 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There are several reasons you might be editing using the IP address of a web host or colocation provider (such as if you are using VPN software or a business network); please use this method of appeal only if you think your IP address is in fact not a web host or colocation provider.</div></div> <p><span class="sysop-show" style="font-size: 85%;"><span style="border:#707070 solid 1px;background-color:#ffe0e0;padding:2px"><b>Administrators:</b></span> The <a href="/wiki/Wikipedia:IP_block_exemption" title="Wikipedia:IP block exemption">IP block exemption</a> user right should only be applied to allow users to edit using web host in exceptional circumstances, and requests should usually be directed to the functionaries team via email. If you intend to give the IPBE user right, a <a href="/wiki/Wikipedia:CheckUser" title="Wikipedia:CheckUser">CheckUser</a> needs to take a look at the account. 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Your current IP address is 8.222.208.146. </p> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>Even when blocked, you will <i>usually</i> still be able to edit your <a href="/wiki/Special:MyTalk" title="Special:MyTalk">user talk page</a>, as well as <a href="/wiki/Wikipedia:Emailing_users" title="Wikipedia:Emailing users">email</a> administrators and other editors. </p> </div> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>For information on how to proceed, please read the <b><a href="/wiki/Wikipedia:Appealing_a_block#Common_questions" title="Wikipedia:Appealing a block">FAQ for blocked users</a></b> and the <a href="/wiki/Wikipedia:Appealing_a_block" title="Wikipedia:Appealing a block">guideline on block appeals</a>. The <a href="/wiki/Wikipedia:Guide_to_appealing_blocks" title="Wikipedia:Guide to appealing blocks">guide to appealing blocks</a> may also be helpful. </p> </div> <p>Other useful links: <a href="/wiki/Wikipedia:Blocking_policy" title="Wikipedia:Blocking policy">Blocking policy</a> · <a href="/wiki/Help:I_have_been_blocked" title="Help:I have been blocked">Help:I have been blocked</a> </p> </div></li><li class="mw-permissionerror-globalblocking-blockedtext-range"> <div id="mw-blocked-text" style="border: 1px solid #AAA; background-color: var(--background-color-warning-subtle, ivory); color: inherit; padding: 1.5em; width: 100%; box-sizing: border-box;"> <div style="text-align: center;"><span style="font-size: 26px;"><span typeof="mw:File"><a href="/wiki/File:Stop_hand_nuvola.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/f/f1/Stop_hand_nuvola.svg/50px-Stop_hand_nuvola.svg.png" decoding="async" width="50" height="50" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/f/f1/Stop_hand_nuvola.svg/75px-Stop_hand_nuvola.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/f/f1/Stop_hand_nuvola.svg/100px-Stop_hand_nuvola.svg.png 2x" data-file-width="240" data-file-height="240" /></a></span><b> This IP address range has been <a href="https://meta.wikimedia.org/wiki/Global_blocks" class="extiw" title="m:Global blocks">globally blocked</a>.</b></span><br /><span style="font-size: 18px;">This does not affect your ability to <i>read</i> Wikipedia pages.</span></div><div class="paragraphbreak" style="margin-top:0.5em"></div><b>Most people who see this message have done nothing wrong.</b> Some kinds of blocks restrict editing from specific service providers or telecom companies in response to recent abuse or vandalism, and can sometimes affect other users who are unrelated to that abuse. Review the information below for assistance if you do not believe that you have done anything wrong.<div class="paragraphbreak" style="margin-top:0.5em"></div><div class="paragraphbreak" style="margin-top:0.5em"></div> <p>This block affects editing on all Wikimedia wikis. </p><p>The IP address or range 8.222.128.0/17 has been globally <a href="/wiki/Wikipedia:Blocking_policy" title="Wikipedia:Blocking policy">blocked</a> by <a href="/wiki/User:Jon_Kolbert" title="User:Jon Kolbert">‪Jon Kolbert‬</a> for the following reason(s): </p> <div style="padding:10px; background:var(--background-color-base, white); color:inherit; border:1px #666 solid;"> <p><a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/NOP" class="extiw" title="m:Special:MyLanguage/NOP">Open proxy/Webhost</a>: See the <a href="https://meta.wikimedia.org/wiki/WM:OP/H" class="extiw" title="m:WM:OP/H">help page</a> if you are affected </p> </div> <p>This block will expire on 15:12, 27 August 2028. Your current IP address is 8.222.208.146. </p> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>Even while globally blocked, you will <i>usually</i> still be able to edit pages on <a href="https://meta.wikimedia.org/wiki/" class="extiw" title="m:">Meta-Wiki</a>. </p> </div> <div class="paragraphbreak" style="margin-top:0.5em"></div><div style="font-size: 16px;"> <p>If you believe you were blocked by mistake, you can find additional information and instructions in the <a href="https://meta.wikimedia.org/wiki/Special:MyLanguage/Stewards/Wizard" class="extiw" title="m:Special:MyLanguage/Stewards/Wizard">Stewards Block Wizard</a>. <a href="/w/index.php?title=MediaWiki:Wikimedia-globalblocking-blockedtext-mistake-email-steward&action=edit&redlink=1" class="new" title="MediaWiki:Wikimedia-globalblocking-blockedtext-mistake-email-steward (page does not exist)">MediaWiki:Wikimedia-globalblocking-blockedtext-mistake-email-steward</a> </p> </div> <p>Other useful links: <a href="https://meta.wikimedia.org/wiki/Global_blocks" class="extiw" title="m:Global blocks">Global blocks</a> · <a href="/wiki/Help:I_have_been_blocked" title="Help:I have been blocked">Help:I have been blocked</a> </p> </div></li></ul><hr /> <div id="viewsourcetext">You can view and copy the source of this page:</div><textarea readonly="" accesskey="," id="wpTextbox1" cols="80" rows="25" style="" class="mw-editfont-monospace" lang="en" dir="ltr" name="wpTextbox1">{{short description|Comprehensive review of research literature using systematic methods}} {{For|the academic journal|Systematic Reviews (journal)}} {{use American English|date=June 2022}} {{use dmy dates|date=June 2022}} [[File:Hierarchy of Evidence.png|thumb|upright=1.2|A systematic review is considered the most trusted form of evidence]] {{Research}} A '''systematic review''' is a [[Literature review|scholarly synthesis]] of the [[evidence]] on a clearly presented topic using critical methods to identify, define and assess research on the topic.<ref name="temple">{{cite web |title=What is a systematic review? |url=https://guides.temple.edu/c.php?g=78618&p=4178713 |publisher=Temple University Libraries |access-date=15 June 2022 |date=6 June 2022}}</ref> A systematic review extracts and interprets data from published studies on the topic (in the [[scientific literature]]), then analyzes, describes, critically appraises and summarizes interpretations into a refined evidence-based conclusion.<ref name=temple/><ref>{{cite journal | vauthors = Armstrong R, Hall BJ, Doyle J, Waters E | title = Cochrane Update. 'Scoping the scope' of a cochrane review | journal = Journal of Public Health | volume = 33 | issue = 1 | pages = 147–150 | date = March 2011 | pmid = 21345890 | doi = 10.1093/pubmed/fdr015 | doi-access = free }}</ref> For example, a systematic review of [[randomized controlled trial]]s is a way of summarizing and implementing [[evidence-based medicine]].<ref name="CEBM_about2">{{cite web|date=2009-11-20|title=What is EBM?|url=http://www.cebm.net/index.aspx?o=1914|archive-url=https://web.archive.org/web/20110406110628/http://www.cebm.net/index.aspx?o=1914|archive-date=2011-04-06|access-date=2011-06-17|publisher=Centre for Evidence Based Medicine}}</ref> Systematic reviews, sometimes along with [[meta-analyses]], are generally considered the highest [[level of evidence]] in [[medical research]].<ref>{{cite journal |last1=Wallace |first1=Sowdhamini S. |last2=Barak |first2=Gal |last3=Truong |first3=Grace |last4=Parker |first4=Michelle W. |title=Hierarchy of Evidence Within the Medical Literature |journal=Hospital Pediatrics |date=1 August 2022 |volume=12 |issue=8 |page=745 |doi=10.1542/hpeds.2022-006690 |pmid=35909178 |language=en |quote=The quality of evidence from medical research is partially deemed by the hierarchy of study designs. On the lowest level, the hierarchy of study designs begins with animal and translational studies and expert opinion, and then ascends to descriptive case reports or case series, followed by analytic observational designs such as cohort studies, then randomized controlled trials, and finally systematic reviews and meta-analyses as the highest quality evidence.}}</ref><ref>{{cite journal |last1=Murad |first1=M Hassan |last2=Asi |first2=Noor |last3=Alsawas |first3=Mouaz |last4=Alahdab |first4=Fares |title=New evidence pyramid |journal=Evidence Based Medicine |date=August 2016 |volume=21 |issue=4 |pages=125–127 |doi=10.1136/ebmed-2016-110401 |pmid=27339128 |language=en |quote=A pyramid has expressed the idea of hierarchy of medical evidence for so long, that not all evidence is the same. Systematic reviews and meta-analyses have been placed at the top of this pyramid for several good reasons.|pmc=4975798 }}</ref> While a systematic review may be applied in the [[Biomedical research|biomedical]] or [[health care]] context, it may also be used where an assessment of a precisely defined subject can advance understanding in a field of research.<ref>{{cite book| vauthors = Ader HJ, Mellenbergh GJ, Hand DJ |title=Advising on Research Methods: A consultant's companion|publisher=Johannes van Kessel Publishing|year=2008|isbn=978-90-79418-02-2|chapter=Methodological quality|chapter-url=https://books.google.com/books?id=LCnOj4ZFyjkC&q=%22Methodological+quality%22}}</ref> A systematic review may examine clinical tests, [[public health]] interventions, environmental interventions,<ref>{{cite journal| vauthors = Bilotta GS, Milner AM, Boyd I |year=2014|title=On the use of systematic reviews to inform environmental policies|journal=Environmental Science & Policy|volume=42|pages=67–77|doi=10.1016/j.envsci.2014.05.010|doi-access=free|bibcode=2014ESPol..42...67B }}</ref> social interventions, [[adverse effects]], qualitative evidence syntheses, methodological reviews, policy reviews, and [[economic evaluation]]s.<ref name="CRD20082">{{cite book|url=https://www.york.ac.uk/media/crd/Systematic_Reviews.pdf|title=Systematic reviews: CRD's guidance for undertaking reviews in health care.|date=2008|publisher=University of York, Centre for Reviews and Dissemination|isbn=978-1-900640-47-3|location=York|access-date=17 June 2011}}</ref><ref>{{cite book|url=http://www.cebma.org/wp-content/uploads/Pettigrew-Roberts-SR-in-the-Soc-Sc.pdf|title=Systematic reviews in the social sciences|vauthors=Petticrew M, Roberts H|date=2006|publisher=Wiley Blackwell|isbn=978-1-4051-2110-1|archive-url=https://web.archive.org/web/20150616034557/http://www.cebma.org/wp-content/uploads/Pettigrew-Roberts-SR-in-the-Soc-Sc.pdf|archive-date=2015-06-16}}</ref> Systematic reviews are closely related to [[meta-analysis|meta-analyses]], and often the same instance will combine both (being published with a subtitle of "a systematic review and meta-analysis"). The distinction between the two is that a meta-analysis uses [[statistics|statistical]] methods to [[inductive reasoning|induce]] a single number from the pooled [[data set]] (such as an [[effect size]]), whereas the strict definition of a systematic review excludes that step. However, in practice, when one is mentioned, the other may often be involved, as it takes a systematic review to assemble the information that a meta-analysis analyzes, and people sometimes refer to an instance as a systematic review, even if it includes the meta-analytical component. An understanding of systematic reviews and how to implement them in practice is common for [[health professional|professionals in health care]], [[public health]], and [[public policy]].<ref name=temple/> Systematic reviews contrast with a type of review often called a narrative review. Systematic reviews and narrative reviews both review the literature (the [[scientific literature]]), but the term ''[[literature review]]'' without further specification refers to a narrative review. ==Characteristics== A systematic review can be designed to provide a thorough summary of current literature relevant to a research question.<ref name=temple/> A systematic review uses a rigorous and transparent approach for research synthesis, with the aim of assessing and, where possible, minimizing bias in the findings. While many systematic reviews are based on an explicit quantitative meta-analysis of available data, there are also qualitative reviews and other types of mixed-methods reviews that adhere to standards for gathering, analyzing, and reporting evidence.<ref>{{cite journal | vauthors = Bearman M, Dawson P | title = Qualitative synthesis and systematic review in health professions education | journal = Medical Education | volume = 47 | issue = 3 | pages = 252–260 | date = March 2013 | pmid = 23398011 | doi = 10.1111/medu.12092 | s2cid = 11042748 | doi-access = free }}</ref> Systematic reviews of [[Quantitative research|quantitative data]] or mixed-method reviews sometimes use statistical techniques (meta-analysis) to combine results of eligible studies. Scoring levels are sometimes used to rate the quality of the evidence depending on the methodology used, although this is discouraged by the [[Cochrane Library]].<ref>{{cite book|url=https://training.cochrane.org/handbook/current|title=Cochrane Handbook for Systematic Reviews of Interventions|date=2019-09-20|website=training.cochrane.org | veditors = Higgins JP, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA |series=version 6.1|pages=section 4.6|language=en|access-date=2020-09-14}}</ref> As evidence rating can be subjective, multiple people may be consulted to resolve any scoring differences between how evidence is rated.<ref>{{cite web| vauthors = Siemieniuk R, Guyatt G |title=What is GRADE?|url=https://bestpractice.bmj.com/info/toolkit/learn-ebm/what-is-grade/|access-date=2020-08-26|website=BMJ Best Practice|language=en}}</ref><ref>{{cite book| vauthors = Adèr HJ |url=https://books.google.com/books?id=LCnOj4ZFyjkC|title=Advising on Research Methods: A Consultant's Companion|date=2008|publisher=Johannes van Kessel Publishing.|isbn=978-90-79418-01-5|language=en}}</ref><ref>{{cite book |url=https://training.cochrane.org/resource/grade-handbook|title=GRADE Handbook|year=2013| veditors = Schünemann H, Brożek J, Guyatt G, Oxman A |language=en|access-date=2020-08-26}}</ref> The [[EPPI-Centre]], [[Cochrane (organisation)|Cochrane]], and the [[The Joanna Briggs Institute|Joanna Briggs Institute]] have been influential in developing methods for combining both qualitative and quantitative research in systematic reviews.<ref name=":1">{{cite journal | vauthors = Flemming K, Booth A, Hannes K, Cargo M, Noyes J | title = Cochrane Qualitative and Implementation Methods Group guidance series-paper 6: reporting guidelines for qualitative, implementation, and process evaluation evidence syntheses | journal = Journal of Clinical Epidemiology | volume = 97 | pages = 79–85 | date = May 2018 | pmid = 29222060 | doi = 10.1016/j.jclinepi.2017.10.022 | url = http://eprints.whiterose.ac.uk/125099/1/1-s2.0-S0895435617313276-main.pdf }}</ref><ref>{{cite journal | vauthors = Harden A, Thomas J, Cargo M, Harris J, Pantoja T, Flemming K, Booth A, Garside R, Hannes K, Noyes J | display-authors = 6 | title = Cochrane Qualitative and Implementation Methods Group guidance series-paper 5: methods for integrating qualitative and implementation evidence within intervention effectiveness reviews | journal = Journal of Clinical Epidemiology | volume = 97 | pages = 70–78 | date = May 2018 | pmid = 29242095 | doi = 10.1016/j.jclinepi.2017.11.029 | url = http://eprints.whiterose.ac.uk/125565/1/CQIMG%20Paper%204.pdf }}</ref><ref>{{cite web|title=EPPI-Centre Home|url=https://eppi.ioe.ac.uk/cms/|access-date=2020-06-29|website=eppi.ioe.ac.uk}}</ref> Several reporting guidelines exist to standardise reporting about how systematic reviews are conducted. Such reporting guidelines are not quality assessment or appraisal tools. The [[Preferred Reporting Items for Systematic Reviews and Meta-Analyses]] (PRISMA) statement<ref name=":2" /> suggests a standardized way to ensure a transparent and complete reporting of systematic reviews, and is now required for this kind of research by more than 170 medical journals worldwide.<ref name=":0" /> The latest version of this commonly used statement corresponds to PRISMA 2020 (the respective article was published in 2021).<ref>{{Cite journal |last1=Page |first1=Matthew J. |last2=McKenzie |first2=Joanne E. |last3=Bossuyt |first3=Patrick M. |last4=Boutron |first4=Isabelle |last5=Hoffmann |first5=Tammy C. |last6=Mulrow |first6=Cynthia D. |last7=Shamseer |first7=Larissa |last8=Tetzlaff |first8=Jennifer M. |last9=Akl |first9=Elie A. |last10=Brennan |first10=Sue E. |last11=Chou |first11=Roger |last12=Glanville |first12=Julie |last13=Grimshaw |first13=Jeremy M. |last14=Hróbjartsson |first14=Asbjørn |last15=Lalu |first15=Manoj M. |date=2021-03-29 |title=The PRISMA 2020 statement: an updated guideline for reporting systematic reviews |journal=BMJ (Clinical Research Ed.) |volume=372 |pages=n71 |doi=10.1136/bmj.n71 |issn=1756-1833 |pmc=8005924 |pmid=33782057}}</ref> Several specialized PRISMA guideline extensions have been developed to support particular types of studies or aspects of the review process, including PRISMA-P for review protocols and PRISMA-ScR for scoping reviews.<ref name=":0" /> A list of PRISMA guideline extensions is hosted by the EQUATOR (Enhancing the QUAlity and Transparency Of health Research) Network.<ref name=":5">{{cite web |title=Preferred Reporting Items for Systematic Reviews and Meta-Analyses: The PRISMA Statement|url=https://www.equator-network.org/reporting-guidelines/prisma/|access-date=2020-06-29|website=www.equator-network.org}}</ref> However, the PRISMA guidelines have been found to be limited to intervention research and the guidelines have to be changed in order to fit non-intervention research. As a result, Non-Interventional, Reproducible, and Open (NIRO) Systematic Reviews was created to counter this limitation.<ref>{{Cite journal |last1=Topor |first1=Marta |last2=Pickering |first2=Jade S. |last3=Mendes |first3=Ana Barbosa |last4=Bishop |first4=Dorothy V. M. |last5=Büttner |first5=Fionn |last6=Elsherif |first6=Mahmoud M. |last7=Evans |first7=Thomas R. |last8=Henderson |first8=Emma L. |last9=Kalandadze |first9=Tamara |last10=Nitschke |first10=Faye T. |last11=Staaks |first11=Janneke P. C. |last12=Akker |first12=Olmo R. van den |last13=Yeung |first13=Siu Kit |last14=Zaneva |first14=Mirela |last15=Lam |first15=Alison |date=2023-07-10 |title=An integrative framework for planning and conducting Non-Intervention, Reproducible, and Open Systematic Reviews (NIRO-SR). |url=https://open.lnu.se/index.php/metapsychology/article/view/2840 |journal=Meta-Psychology |language=en |volume=7 |doi=10.15626/MP.2021.2840 |issn=2003-2714|doi-access=free |hdl=11250/3106491 |hdl-access=free }}</ref> For qualitative reviews, reporting guidelines include ENTREQ (Enhancing transparency in reporting the synthesis of qualitative research) for qualitative evidence syntheses; RAMESES (Realist And MEta-narrative Evidence Syntheses: Evolving Standards) for meta-narrative and realist reviews;<ref>{{cite journal | vauthors = Wong G, Greenhalgh T, Westhorp G, Buckingham J, Pawson R | title = RAMESES publication standards: meta-narrative reviews | journal = Journal of Advanced Nursing | volume = 69 | issue = 5 | pages = 987–1004 | date = May 2013 | pmid = 23356699 | pmc = 3558334 | doi = 10.1111/jan.12092 }}</ref><ref>{{cite journal | vauthors = Wong G, Greenhalgh T, Westhorp G, Buckingham J, Pawson R | title = RAMESES publication standards: realist syntheses | journal = Journal of Advanced Nursing | volume = 69 | issue = 5 | pages = 1005–1022 | date = May 2013 | pmid = 23356726 | pmc = 3558331 | doi = 10.1111/jan.12095 }}</ref> and eMERGe (Improving reporting of Meta-Ethnography) for meta-[[Ethnography|ethnograph]].<ref name=":1" /> Developments in systematic reviews during the 21st century included realist reviews and the meta-narrative approach, both of which addressed problems of variation in methods and heterogeneity existing on some subjects.<ref name=":3" /><ref name=":4" /> == Types == There are over 30 types of systematic review and '''Table 1''' below non-exhaustingly summarises some of these.<ref name=":0">{{cite journal | vauthors = Grant MJ, Booth A | title = A typology of reviews: an analysis of 14 review types and associated methodologies | journal = Health Information and Libraries Journal | volume = 26 | issue = 2 | pages = 91–108 | date = June 2009 | pmid = 19490148 | doi = 10.1111/j.1471-1842.2009.00848.x | doi-access = free }}</ref><ref name=":2">{{cite book| vauthors = Booth A, Noyes J, Flemming K, Gerhardus A, Wahlster P, Van Der Wilt GJ, Mozygemba K, Refolo P, Sacchini D, Tummers M, Rehfuess E | display-authors = 6 |url=http://worldcat.org/oclc/944453327|title=Guidance on choosing qualitative evidence synthesis methods for use in health technology assessments of complex interventions |date=2016 |page=32 |oclc=944453327 }}</ref> There is not always consensus on the boundaries and distinctions between the approaches described below. {| class="wikitable" |+Table 1: A summary of some of the types of systematic review !Review type !Summary |- |Mapping review/systematic map |A mapping review maps existing literature and categorizes data. The method characterizes the quantity and quality of literature, including by study design and other features. Mapping reviews can be used to identify the need for primary or secondary research.<ref name=":0" /> |- |Meta-analysis |A meta-analysis is a statistical analysis that combines the results of multiple quantitative studies. Using statistical methods, results are combined to provide evidence from multiple studies. The two types of data generally used for meta-analysis in health research are individual participant data and aggregate data (such as odds ratios or relative risks). |- |Mixed studies review/mixed methods review |Refers to any combination of methods where one significant stage is a literature review (often systematic). It can also refer to a combination of review approaches, such as combining quantitative with qualitative research.<ref name=":0" /> |- |Qualitative systematic review/qualitative evidence synthesis |This method integrates or compares findings from qualitative studies. The method can include 'coding' the data and looking for 'themes' or 'constructs' across studies. Multiple authors may improve the 'validity' of the data by potentially reducing individual bias.<ref name=":0" /> |- |[[Rapid reviews|Rapid review]] |An assessment of what is already known about a policy or practice issue, which uses systematic review methods to search for and critically appraise existing research. Rapid reviews are still a systematic review, however parts of the process may be simplified or omitted in order to increase rapidity.<ref>{{cite web|title=What is a rapid review? Systematic Review Library Guides at CQ University|url=https://libguides.library.cqu.edu.au/c.php?g=849703&p=6154326|archive-url=https://web.archive.org/web/20200916051435/https://libguides.library.cqu.edu.au/c.php?g=849703&p=6154326|archive-date=2020-09-16|access-date=2020-09-16|website=library.cqu.edu.au}}</ref> Rapid reviews were used during the COVID-19 pandemic.<ref>{{cite web|title=Home|url=https://covidrapidreviews.cochrane.org/welcome|access-date=2020-07-01|website=covidrapidreviews.cochrane.org|language=en}}</ref> |- |Systematic review |A systematic search for data using a repeatable method. It includes appraising the data (for example, the quality of the data) and a synthesis of research data. |- |Systematic search and review |Combines methods from a 'critical review' with a comprehensive search process. This review type is usually used to address broad questions to produce the most appropriate evidence synthesis. This method may or may not include quality assessment of data sources.<ref name=":0" /> |- |Systematized review |Include elements of the systematic review process, but searching is often not as comprehensive as a systematic review and may not include quality assessments of data sources. |} ===Scoping reviews=== Scoping reviews are distinct from systematic reviews in several ways. A scoping review is an attempt to search for concepts by [[Map (mathematics)|mapping]] the language and data which surrounds those concepts and [[Iterative and incremental development|adjusting the search method iteratively]] to synthesize evidence and assess the scope of an area of inquiry.<ref name=":3">{{cite journal| vauthors = Arksey H, O'Malley L |year=2005|title=Scoping studies: Towards a methodological framework|journal=International Journal of Social Research Methodology|volume=8|pages=19–32|doi=10.1080/1364557032000119616|hdl=11250/2477738 |s2cid=12719181|url=https://eprints.whiterose.ac.uk/1618/1/Scopingstudies.pdf}}</ref><ref name=":4">{{cite web|title=PRISMA|url=http://www.prisma-statement.org/Extensions/ScopingReviews|access-date=2020-07-01|website=www.prisma-statement.org}}</ref> This can mean that the [[concept search]] and method (including [[data extraction]], organisation and analysis) are refined throughout the process, sometimes requiring deviations from any protocol or original research plan.<ref name="Peters 141–146">{{cite journal | vauthors = Peters MD, Godfrey CM, Khalil H, McInerney P, Parker D, Soares CB | title = Guidance for conducting systematic scoping reviews | journal = International Journal of Evidence-Based Healthcare | volume = 13 | issue = 3 | pages = 141–146 | date = September 2015 | pmid = 26134548 | doi = 10.1097/XEB.0000000000000050 | s2cid = 8860037 | url = https://unisa.alma.exlibrisgroup.com/view/delivery/61USOUTHAUS_INST/12229029930001831 | doi-access = free }}</ref><ref name="Scoping studies: advancing the meth">{{cite journal | vauthors = Levac D, Colquhoun H, O'Brien KK | title = Scoping studies: advancing the methodology | journal = Implementation Science | volume = 5 | issue = 1 | pages = 69 | date = September 2010 | pmid = 20854677 | pmc = 2954944 | doi = 10.1186/1748-5908-5-69 | doi-access = free }}</ref> A scoping review may often be a preliminary stage before a systematic review, which 'scopes' out an area of inquiry and maps the language and key concepts to determine if a systematic review is possible or appropriate, or to lay the groundwork for a full systematic review. The goal can be to assess how much data or evidence is available regarding a certain area of interest.<ref name="Peters 141–146" /><ref name = "Colquhoun_2014">{{cite journal | vauthors = Colquhoun HL, Levac D, O'Brien KK, Straus S, Tricco AC, Perrier L, Kastner M, Moher D | display-authors = 6 | title = Scoping reviews: time for clarity in definition, methods, and reporting | journal = Journal of Clinical Epidemiology | volume = 67 | issue = 12 | pages = 1291–1294 | date = December 2014 | pmid = 25034198 | doi = 10.1016/j.jclinepi.2014.03.013 | hdl-access = free | hdl = 1807/73365 | s2cid = 205843946 }}</ref> This process is further complicated if it is [[Map (mathematics)|mapping]] concepts across multiple languages or cultures. As a scoping review should be systematically conducted and reported (with a transparent and repeatable method), some academic publishers categorize them as a kind of 'systematic review', which may cause confusion. Scoping reviews are helpful when it is not possible to carry out a systematic synthesis of research findings, for example, when there are no published clinical trials in the area of inquiry. Scoping reviews are helpful when determining if it is possible or appropriate to carry out a systematic review, and are a useful method when an area of inquiry is very broad,<ref>{{cite journal | vauthors = Nunn JS, Tiller J, Fransquet P, Lacaze P | title = Public Involvement in Global Genomics Research: A Scoping Review | journal = Frontiers in Public Health | volume = 7 | pages = 79 | date = 2019 | pmid = 31024880 | pmc = 6467093 | doi = 10.3389/fpubh.2019.00079 | doi-access = free }}</ref> for example, exploring how the public are involved in all stages systematic reviews.<ref name="ReferenceA2">{{cite journal | vauthors = Pollock A, Campbell P, Struthers C, Synnot A, Nunn J, Hill S, Goodare H, Watts C, Morley R | display-authors = 6 | title = Stakeholder involvement in systematic reviews: a protocol for a systematic review of methods, outcomes and effects | journal = Research Involvement and Engagement | volume = 3 | issue = 1 | pages = 9 | date = 2017-04-21 | pmid = 29062534 | pmc = 5611627 | doi = 10.1186/s40900-017-0060-4 | doi-access = free }}</ref> There is still a lack of clarity when defining the exact method of a scoping review as it is both an [[Iterative and incremental development|iterative process]] and is still relatively new.<ref>{{cite journal | vauthors = Munn Z, Peters MD, Stern C, Tufanaru C, McArthur A, Aromataris E | title = Systematic review or scoping review? Guidance for authors when choosing between a systematic or scoping review approach | journal = BMC Medical Research Methodology | volume = 18 | issue = 1 | pages = 143 | date = November 2018 | pmid = 30453902 | pmc = 6245623 | doi = 10.1186/s12874-018-0611-x | doi-access = free }}</ref> There have been several attempts to improve the standardisation of the method,<ref name="Scoping studies: advancing the meth"/><ref name="Peters 141–146"/><ref name = "Colquhoun_2014" /><ref>{{cite journal| vauthors = Arksey H, O'Malley L |date=2005-02-01|title=Scoping studies: towards a methodological framework|journal=International Journal of Social Research Methodology|volume=8|issue=1|pages=19–32|doi=10.1080/1364557032000119616 |hdl=11250/2477738 |s2cid=12719181|url=https://eprints.whiterose.ac.uk/1618/1/Scopingstudies.pdf}}</ref> for example via a [[Preferred Reporting Items for Systematic Reviews and Meta-Analyses|Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)]] guideline extension for scoping reviews (PRISMA-ScR).<ref>{{cite journal | vauthors = Tricco AC, Lillie E, Zarin W, O'Brien KK, Colquhoun H, Levac D, Moher D, Peters MD, Horsley T, Weeks L, Hempel S, Akl EA, Chang C, McGowan J, Stewart L, Hartling L, Aldcroft A, Wilson MG, Garritty C, Lewin S, Godfrey CM, Macdonald MT, Langlois EV, Soares-Weiser K, Moriarty J, Clifford T, Tunçalp Ö, Straus SE | display-authors = 6 | title = PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and Explanation | journal = Annals of Internal Medicine | volume = 169 | issue = 7 | pages = 467–473 | date = October 2018 | pmid = 30178033 | doi = 10.7326/M18-0850 | s2cid = 52150954 | url = https://eprints.whiterose.ac.uk/136633/1/PRISMA_ScR_Manuscript_July6th_clean_1_.pdf }}</ref> [[PROSPERO]] (the International Prospective Register of Systematic Reviews) does not permit the submission of protocols of scoping reviews,<ref>{{cite web|title=PROSPERO|url=https://www.crd.york.ac.uk/prospero/#aboutregpage|access-date=2019-02-24|work=Centre for Reviews and Dissemination|publisher=University of York}}</ref> although some journals will publish protocols for scoping reviews.<ref name="ReferenceA2" /> == Stages == While there are multiple kinds of systematic review methods, the main stages of a review can be summarised as follows: === Defining the research question === Some reported that the 'best practices' involve 'defining an answerable question' and publishing the protocol of the review before initiating it to reduce the risk of unplanned research duplication and to enable transparency and consistency between methodology and protocol.<ref name="Cochrane storyboard2">{{cite web|title=Animated Storyboard: What Are Systematic Reviews?|url=https://cccrg.cochrane.org/animated-storyboard-what-are-systematic-reviews|access-date=1 June 2016|website=cccrg.cochrane.org|publisher=Cochrane Consumers and Communication}}</ref><ref>{{cite journal | vauthors = Moher D, Shamseer L, Clarke M, Ghersi D, Liberati A, Petticrew M, Shekelle P, Stewart LA | display-authors = 6 | title = Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement | journal = Systematic Reviews | volume = 4 | issue = 1 | pages = 1 | date = January 2015 | pmid = 25554246 | pmc = 4320440 | doi = 10.1186/2046-4053-4-1 | doi-access = free }}</ref> Clinical reviews of quantitative data are often structured using the mnemonic [[PICO process|PICO]], which stands for 'Population or Problem', 'Intervention or Exposure', 'Comparison', and 'Outcome', with other variations existing for other kinds of research. For qualitative reviews, PICo is 'Population or Problem', 'Interest', and 'Context'. === Searching for sources === Relevant criteria can include selecting research that is of good quality and answers the defined question.<ref name="Cochrane storyboard2" /> The search strategy should be designed to retrieve literature that matches the protocol's specified inclusion and exclusion criteria. The methodology section of a systematic review should list all of the databases and citation indices that were searched. The titles and abstracts of identified articles can be checked against predetermined criteria for eligibility and relevance. Each included study may be assigned an objective assessment of methodological quality, preferably by using methods conforming to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement,<ref name=":5" /> or the standards of Cochrane.<ref name="CochraneHandbook2">{{cite web|title=Cochrane handbook for systematic reviews of interventions, version 5.1.0 (updated March 2011)|url=http://handbook.cochrane.org|access-date=2 June 2016|publisher=The Cochrane Collaboration|veditors=Higgins JP, Green S}}</ref> Common information sources used in searches include scholarly databases of peer-reviewed articles such as [[MEDLINE]], [[Web of Science]], [[Embase]], and [[PubMed]], as well as sources of unpublished literature such as clinical trial registries and [[grey literature]] collections. Key references can also be yielded through additional methods such as citation searching, reference list checking (related to a search method called '[[pearl growing]]'), manually searching information sources not indexed in the major electronic databases (sometimes called 'hand-searching'),<ref>{{cite web|title=5. Handsearching|url=https://training.cochrane.org/resource/tsc-induction-mentoring-training-guide/5-handsearching|access-date=2020-09-14|website=training.cochrane.org|language=en}}</ref> and directly contacting experts in the field.<ref>{{cite journal | vauthors = Papaioannou D, Sutton A, Carroll C, Booth A, Wong R | title = Literature searching for social science systematic reviews: consideration of a range of search techniques | journal = Health Information and Libraries Journal | volume = 27 | issue = 2 | pages = 114–122 | date = June 2010 | pmid = 20565552 | doi = 10.1111/j.1471-1842.2009.00863.x | doi-access = free }}</ref> To be systematic, searchers must use a combination of search skills and tools such as database subject headings, keyword searching, [[Logical connective|Boolean operators]], and proximity searching while attempting to balance sensitivity (systematicity) and precision (accuracy). Inviting and involving an experienced information professional or librarian can improve the quality of systematic review search strategies and reporting.<ref>{{cite journal | vauthors = Rethlefsen ML, Farrell AM, Osterhaus Trzasko LC, Brigham TJ | title = Librarian co-authors correlated with higher quality reported search strategies in general internal medicine systematic reviews | journal = Journal of Clinical Epidemiology | volume = 68 | issue = 6 | pages = 617–626 | date = June 2015 | pmid = 25766056 | doi = 10.1016/j.jclinepi.2014.11.025 }}</ref><ref>{{cite journal | vauthors = Koffel JB | title = Use of recommended search strategies in systematic reviews and the impact of librarian involvement: a cross-sectional survey of recent authors | journal = PLOS ONE | volume = 10 | issue = 5 | pages = e0125931 | date = 2015-05-04 | pmid = 25938454 | pmc = 4418838 | doi = 10.1371/journal.pone.0125931 | doi-access = free | bibcode = 2015PLoSO..1025931K }}</ref><ref>{{cite journal | vauthors = Meert D, Torabi N, Costella J | title = Impact of librarians on reporting of the literature searching component of pediatric systematic reviews | journal = Journal of the Medical Library Association | volume = 104 | issue = 4 | pages = 267–277 | date = October 2016 | pmid = 27822147 | pmc = 5079487 | doi = 10.5195/jmla.2016.139 }}</ref><ref>{{cite journal | vauthors = Li L, Tian J, Tian H, Moher D, Liang F, Jiang T, Yao L, Yang K | display-authors = 6 | title = Network meta-analyses could be improved by searching more sources and by involving a librarian | journal = Journal of Clinical Epidemiology | volume = 67 | issue = 9 | pages = 1001–1007 | date = September 2014 | pmid = 24841794 | doi = 10.1016/j.jclinepi.2014.04.003 }}</ref><ref>{{cite journal | vauthors = Rethlefsen ML, Murad MH, Livingston EH | title = Engaging medical librarians to improve the quality of review articles | journal = JAMA | volume = 312 | issue = 10 | pages = 999–1000 | date = September 2014 | pmid = 25203078 | doi = 10.1001/jama.2014.9263 }}</ref> === 'Extraction' of relevant data === [[File:Extraction machine.gif|thumb|440x440px|A visualisation of data being 'extracted' and 'combined' in a Cochrane intervention effect review where a meta-analysis is possible<ref name=":8">{{cite web|title=Animated Storyboard: What Are Systematic Reviews?|url=https://cccrg.cochrane.org/animated-storyboard-what-are-systematic-reviews|access-date=2020-11-24|website=cccrg.cochrane.org|language=en}}</ref>]] Relevant data are 'extracted' from the data sources according to the review method. The data extraction method is specific to the kind of data, and data extracted on 'outcomes' is only relevant to certain types of reviews. For example, a systematic review of clinical trials might extract data about how the research was done (often called the method or 'intervention'), who participated in the research (including how many people), how it was paid for (for example, funding sources) and what happened (the outcomes).<ref name="Cochrane storyboard2" /> Relevant data are being extracted and 'combined' in an intervention effect review, where a meta-analysis is possible.<ref name=":8" /> === Assess the eligibility of the data === This stage involves assessing the eligibility of data for inclusion in the review by judging it against criteria identified at the first stage.<ref name="Cochrane storyboard2" /> This can include assessing if a data source meets the eligibility criteria and recording why decisions about inclusion or exclusion in the review were made. Software programmes can be used to support the selection process, including text mining tools and machine learning, which can automate aspects of the process.<ref>{{cite book | url=https://training.cochrane.org/handbook/current|title=Cochrane Handbook for Systematic Reviews of Interventions|date=2019-09-20|website=training.cochrane.org| veditors = Higgins JP, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA |series=version 6.1|pages=section 4.6|no-pp=y|language=en|chapter=Chapter 4: Searching for and selecting studies|access-date=2020-09-14 |chapter-url=https://training.cochrane.org/handbook/current/chapter-04#section-4-6}}</ref> The 'Systematic Review Toolbox' is a community-driven, web-based catalog of tools, to help reviewers chose appropriate tools for reviews.<ref>{{cite book| vauthors = Marshall C, Brereton P |title=Proceedings of the 19th International Conference on Evaluation and Assessment in Software Engineering |chapter=Systematic review toolbox |date=2015-04-27|series=EASE '15|location=Nanjing, China|publisher=Association for Computing Machinery|pages=1–6|doi=10.1145/2745802.2745824|isbn=978-1-4503-3350-4|s2cid=6679820}}</ref> === Analyse and combine the data === Analysing and combining data can provide an overall result from all the data. Because this combined result may use qualitative or quantitative data from all eligible sources of data, it is considered more reliable as it provides better evidence, as the more data included in reviews, the more confident we can be of conclusions. When appropriate, some systematic reviews include a meta-analysis, which uses statistical methods to combine data from multiple sources. A review might use quantitative data, or might employ a qualitative meta-synthesis, which synthesises data from qualitative studies. A review may also bring together the findings from quantitative and qualitative studies in a mixed methods or overarching synthesis.<ref>{{cite journal | vauthors = Thompson Coon J, Gwernan-Jones R, Garside R, Nunns M, Shaw L, Melendez-Torres GJ, Moore D | title = Developing methods for the overarching synthesis of quantitative and qualitative evidence: The interweave synthesis approach | journal = Research Synthesis Methods | volume = 11 | issue = 4 | pages = 507–521 | date = July 2020 | pmid = 31725951 | pmc = 7383598 | doi = 10.1002/jrsm.1383 }}</ref> The combination of data from a meta-analysis can sometimes be visualised. One method uses a [[forest plot]] (also called a [[blobbogram]]).<ref name="Cochrane storyboard2" /> In an intervention effect review, the diamond in the 'forest plot' represents the combined results of all the data included.<ref name="Cochrane storyboard2" /> An example of a 'forest plot' is the Cochrane Collaboration logo.<ref name="Cochrane storyboard2" /> The logo is a forest plot of one of the first reviews which showed that corticosteroids given to women who are about to give birth prematurely can save the life of the newborn child.<ref>{{cite web|title=The difference we make|url=https://www.cochrane.org/about-us/difference-we-make|access-date=2019-03-08|website=www.cochrane.org}}</ref> Recent visualisation innovations include the albatross plot, which plots [[p-value]]s against sample sizes, with approximate effect-size contours superimposed to facilitate analysis.<ref>{{cite journal | vauthors = Higgins JP, López-López JA, Becker BJ, Davies SR, Dawson S, Grimshaw JM, McGuinness LA, Moore TH, Rehfuess EA, Thomas J, Caldwell DM | display-authors = 6 | title = Synthesising quantitative evidence in systematic reviews of complex health interventions | journal = BMJ Global Health | volume = 4 | issue = Suppl 1 | pages = e000858 | date = 2019-01-01 | pmid = 30775014 | pmc = 6350707 | doi = 10.1136/bmjgh-2018-000858 }}</ref> The contours can be used to infer effect sizes from studies that have been analysed and reported in diverse ways. Such visualisations may have advantages over other types when reviewing complex interventions. === Communication and dissemination === Once these stages are complete, the review may be published, disseminated, and translated into practice after being adopted as evidence. The UK [[National Institute for Health and Care Research|National Institute for Health Research]] (NIHR) defines dissemination as "getting the findings of research to the people who can make use of them to maximise the benefit of the research without delay".<ref>{{Cite web |title=How to disseminate your research |url=https://www.nihr.ac.uk/documents/how-to-disseminate-your-research/19951#:~:text=Principles%20of%20good%20dissemination,-Stakeholder%20engagement:%20Work&text=Format:%20Produce%20targeted%20outputs%20that,or%20local%20levels%20as%20appropriate |access-date=2022-05-20 |website=www.nihr.ac.uk}}</ref> Some users do not have time to invest in reading large and complex documents and/or may lack awareness or be unable to access newly published research. Researchers are, therefore, developing skills to use creative communication methods such as illustrations, blogs, infographics, and board games to share the findings of systematic reviews.<ref>{{cite journal | vauthors = Coon JT, Orr N, Shaw L, Hunt H, Garside R, Nunns M, Gröppel-Wegener A, Whear B | display-authors = 6 | title = Bursting out of our bubble: using creative techniques to communicate within the systematic review process and beyond | journal = Systematic Reviews | volume = 11 | issue = 1 | pages = 56 | date = April 2022 | pmid = 35379331 | pmc = 8977563 | doi = 10.1186/s13643-022-01935-2 | doi-access = free }}</ref> == Automation == Living systematic reviews are a newer kind of semi-automated, up-to-date online summaries of research that are updated as new research becomes available.<ref name="Systematic review automation techno">{{cite journal | vauthors = Tsafnat G, Glasziou P, Choong MK, Dunn A, Galgani F, Coiera E | title = Systematic review automation technologies | journal = Systematic Reviews | volume = 3 | issue = 1 | pages = 74 | date = July 2014 | pmid = 25005128 | pmc = 4100748 | doi = 10.1186/2046-4053-3-74 | doi-access = free }}</ref> The difference between a living systematic review and a conventional systematic review is the publication format. Living systematic reviews are "dynamic, persistent, online-only evidence summaries, which are updated rapidly and frequently".<ref name="Living systematic reviews: an emerg">{{cite journal | vauthors = Elliott JH, Turner T, Clavisi O, Thomas J, Higgins JP, Mavergames C, Gruen RL | title = Living systematic reviews: an emerging opportunity to narrow the evidence-practice gap | journal = PLOS Medicine | volume = 11 | issue = 2 | pages = e1001603 | date = February 2014 | pmid = 24558353 | pmc = 3928029 | doi = 10.1371/journal.pmed.1001603 | doi-access = free }}</ref> The automation or semi-automation of the systematic process itself is increasingly being explored. While little evidence exists to demonstrate it is as accurate or involves less manual effort, efforts that promote training and using [[artificial intelligence]] for the process are increasing.<ref>{{cite journal | vauthors = Reddy SM, Patel S, Weyrich M, Fenton J, Viswanathan M | title = Comparison of a traditional systematic review approach with review-of-reviews and semi-automation as strategies to update the evidence | journal = Systematic Reviews | volume = 9 | issue = 1 | pages = 243 | date = October 2020 | pmid = 33076975 | pmc = 7574591 | doi = 10.1186/s13643-020-01450-2 | doi-access = free }}</ref><ref name="Systematic review automation techno" /> ==Research fields== === Health and medicine === ==== Current use of systematic reviews in medicine ==== Many organisations around the world use systematic reviews, with the methodology depending on the guidelines being followed. Organisations which use systematic reviews in medicine and human health include the [[National Institute for Health and Care Excellence]] (NICE, UK), the [[Agency for Healthcare Research and Quality]] (AHRQ, US), and the [[World Health Organization]]. Most notable among international organisations is [[Cochrane Collaboration|Cochrane]], a group of over 37,000 specialists in healthcare who systematically review randomised trials of the effects of prevention, treatments, and rehabilitation as well as health systems interventions. They sometimes also include the results of other types of research. Cochrane Reviews are published in ''The Cochrane Database of Systematic Reviews'' section of the [[Cochrane Library]]. The 2015 [[impact factor]] for ''The Cochrane Database of Systematic Reviews'' was 6.103, and it was ranked 12th in the Medicine, General & Internal category.<ref>The Cochrane Library. [http://www.cochrane.org/news/2015-impact-factor-released-cochrane-database-systematic-reviews 2015 impact factor. Cochrane Database of Systematic Reviews (CDSR)] {{Webarchive|url=https://web.archive.org/web/20160702164207/http://www.cochrane.org/news/2015-impact-factor-released-cochrane-database-systematic-reviews |date=2 July 2016 }} Retrieved 2016-07-20.</ref> There are several types of systematic reviews, including:<ref>[http://tech.cochrane.org/revman <nowiki>Review Manager (RevMan) [Computer program]</nowiki>]. Version 5.2. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2012.</ref><ref>{{cite web |title=Main page|url=https://www.cochranelibrary.com/|website=Cochrane Library|language=en}}</ref><ref>{{cite journal | vauthors = Silva V, Grande AJ, Carvalho AP, Martimbianco AL, Riera R | title = Overview of systematic reviews - a new type of study. Part II | journal = Sao Paulo Medical Journal = Revista Paulista de Medicina | volume = 133 | issue = 3 | pages = 206–217 | year = 2015 | pmid = 25388685 | doi = 10.1590/1516-3180.2013.8150015 | doi-access = free | pmc = 10876375 }}</ref><ref>{{cite journal | vauthors = Silva V, Grande AJ, Martimbianco AL, Riera R, Carvalho AP | title = Overview of systematic reviews - a new type of study: part I: why and for whom? | journal = Sao Paulo Medical Journal = Revista Paulista de Medicina | volume = 130 | issue = 6 | pages = 398–404 | year = 2012 | pmid = 23338737 | doi = 10.1590/S1516-31802012000600007 | pmc = 10522321 | doi-access = free }}</ref> # '''Intervention reviews''' assess the benefits and harms of interventions used in healthcare and health policy. # '''Diagnostic test accuracy reviews''' assess how well a diagnostic test performs in diagnosing and detecting a particular disease. For conducting diagnostic test accuracy reviews, free software such as MetaDTA and CAST-HSROC in the graphical user interface is available.<ref>{{cite journal | vauthors = Freeman SC, Kerby CR, Patel A, Cooper NJ, Quinn T, Sutton AJ | title = Development of an interactive web-based tool to conduct and interrogate meta-analysis of diagnostic test accuracy studies: MetaDTA | journal = BMC Medical Research Methodology | volume = 19 | issue = 1 | pages = 81 | date = April 2019 | pmid = 30999861 | pmc = 6471890 | doi = 10.1186/s12874-019-0724-x | doi-access = free }}</ref><ref>{{cite journal | vauthors = Banno M, Tsujimoto Y, Luo Y, Miyakoshi C, Kataoka Y | title = CAST-HSROC: A Web Application for Calculating the Summary Points of Diagnostic Test Accuracy From the Hierarchical Summary Receiver Operating Characteristic Model | journal = Cureus | volume = 13 | issue = 2 | pages = e13257 | date = February 2021 | pmid = 33717762 | pmc = 7953362 | doi = 10.7759/cureus.13257 | doi-access = free }}</ref> # '''Methodology reviews''' address issues relevant to how systematic reviews and clinical trials are conducted and reported. # '''Qualitative reviews''' synthesize qualitative evidence to address questions on aspects other than effectiveness. # '''Prognosis reviews''' address the probable course or future outcome(s) of people with a health problem. # '''Overviews of Systematic Reviews''' ('''OoRs''') compile multiple pieces of evidence from systematic reviews into a single accessible document, sometimes referred to as [[Umbrella review|''umbrella reviews'']]. # '''Living systematic reviews''' are continually updated, incorporating relevant new evidence as it becomes available.<ref>{{cite web|title=Living systematic reviews|url=https://community.cochrane.org/review-production/production-resources/living-systematic-reviews|access-date=2020-07-01|website=community.cochrane.org|language=en}}</ref> # '''Rapid reviews''' are a form of knowledge synthesis that "accelerates the process of conducting a traditional systematic review through streamlining or omitting specific methods to produce evidence for stakeholders in a resource-efficient manner".<ref>{{cite news|title=Cochrane's work on Rapid Reviews in response to COVID-19|url=https://www.cochrane.org/cochranes-work-rapid-reviews-response-covid-19|access-date=2020-07-01|website=www.cochrane.org|language=en}}</ref> # '''Reviews of complex health interventions in complex systems''' are to improve evidence synthesis and guideline development.<ref>{{cite journal | vauthors = Norris SL, Rehfuess EA, Smith H, Tunçalp Ö, Grimshaw JM, Ford NP, Portela A | title = Complex health interventions in complex systems: improving the process and methods for evidence-informed health decisions | journal = BMJ Global Health | volume = 4 | issue = Suppl 1 | pages = e000963 | date = 2019-01-01 | pmid = 30775018 | pmc = 6350736 | doi = 10.1136/bmjgh-2018-000963 }}</ref> ==== Patient and public involvement in systematic reviews ==== {{Further information|Patient and public involvement}} There are various ways patients and the public can be involved in producing systematic reviews and other outputs. Tasks for public members can be organised as 'entry level' or higher. Tasks include: * Joining a collaborative volunteer effort to help categorise and summarise healthcare evidence<ref>{{cite web|title=Cochrane crowd|url=http://crowd.cochrane.org/index.html|access-date=2019-02-14|website=crowd.cochrane.org}}</ref> * Data extraction and risk of bias assessment * Translation of reviews into other languages A systematic review of how people were involved in systematic reviews aimed to document the evidence-base relating to stakeholder involvement in systematic reviews and to use this evidence to describe how stakeholders have been involved in systematic reviews.<ref>{{cite journal | vauthors = Pollock A, Campbell P, Struthers C, Synnot A, Nunn J, Hill S, Goodare H, Morris J, Watts C, Morley R | display-authors = 6 | title = Stakeholder involvement in systematic reviews: a scoping review | journal = Systematic Reviews | volume = 7 | issue = 1 | pages = 208 | date = November 2018 | pmid = 30474560 | pmc = 6260873 | doi = 10.1186/s13643-018-0852-0 | doi-access = free }}</ref> Thirty percent involved patients and/or carers. The ACTIVE framework provides a way to describe how people are involved in systematic review and may be used as a way to support systematic review authors in planning people's involvement.<ref>{{cite journal | vauthors = Pollock A, Campbell P, Struthers C, Synnot A, Nunn J, Hill S, Goodare H, Morris J, Watts C, Morley R | display-authors = 6 | title = Development of the ACTIVE framework to describe stakeholder involvement in systematic reviews | journal = Journal of Health Services Research & Policy | volume = 24 | issue = 4 | pages = 245–255 | date = October 2019 | pmid = 30997859 | doi = 10.1177/1355819619841647 | s2cid = 121348214 | url = https://discovery.dundee.ac.uk/ws/files/31267968/JHSRP_ACTIVE_framework_final_author_accepted_version.pdf }}</ref> Standardised Data on Initiatives (STARDIT) is another proposed way of reporting who has been involved in which tasks during research, including systematic reviews.<ref>[Pre-print] {{cite journal | vauthors = Nunn J, Shafee T, Chang S, Stephens R, Elliott J, Oliver S, John D, Smith M, Orr N |title=Standardised Data on Initiatives - STARDIT: Alpha Version|url=https://osf.io/5q47h/|access-date=2020-08-20|website=osf.io|doi=10.31219/osf.io/5q47h |s2cid=242815262}}</ref><ref>{{cite journal | vauthors = Nunn JS, Shafee T, Chang S, Stephens R, Elliott J, Oliver S, John D, Smith M, Orr N, Preston J, Borthwick J, van Vlijmen T, Ansell J, Houyez F, de Sousa MS, Plotz RD, Oliver JL, Golumbic Y, Macniven R, Wines S, Borda A, da Silva Hyldmo H, Hsing PY, Denis L, Thompson C | display-authors = 6 | title = Standardised data on initiatives-STARDIT: Beta version | journal = Research Involvement and Engagement | volume = 8 | issue = 1 | pages = 31 | date = July 2022 | pmid = 35854364 | pmc = 9294764 | doi = 10.1186/s40900-022-00363-9 | doi-access = free }}</ref> There has been some criticism of how Cochrane prioritises systematic reviews.<ref>{{cite journal | title = Has Cochrane lost its way? | journal = BMJ | volume = 364 | pages = k5302 | date = 2019-01-03 | pmid = 30606713 | doi = 10.1136/bmj.k5302 | s2cid = 58623482 | last1 = Newman | first1 = Melanie }}</ref> Cochrane has a project that involved people in helping identify research priorities to inform Cochrane Reviews.<ref>{{cite journal | vauthors = Synnot AJ, Tong A, Bragge P, Lowe D, Nunn JS, O'Sullivan M, Horvat L, Kay D, Ghersi D, McDonald S, Poole N, Bourke N, Lannin NA, Vadasz D, Oliver S, Carey K, Hill SJ | display-authors = 6 | title = Selecting, refining and identifying priority Cochrane Reviews in health communication and participation in partnership with consumers and other stakeholders | journal = Health Research Policy and Systems | volume = 17 | issue = 1 | pages = 45 | date = April 2019 | pmid = 31036016 | pmc = 6489310 | doi = 10.1186/s12961-019-0444-z | doi-access = free }}</ref><ref>{{cite journal | vauthors = Synnot A, Bragge P, Lowe D, Nunn JS, O'Sullivan M, Horvat L, Tong A, Kay D, Ghersi D, McDonald S, Poole N, Bourke N, Lannin N, Vadasz D, Oliver S, Carey K, Hill SJ | display-authors = 6 | title = Research priorities in health communication and participation: international survey of consumers and other stakeholders | journal = BMJ Open | volume = 8 | issue = 5 | pages = e019481 | date = May 2018 | pmid = 29739780 | pmc = 5942413 | doi = 10.1136/bmjopen-2017-019481 }}</ref> In 2014, the [[Cochrane (organisation)#Wikipedia|Cochrane–Wikipedia]] partnership was formalised.<ref>{{cite web|title=The Cochrane-Wikipedia partnership in 2016|url=https://www.cochrane.org/news/cochrane-wikipedia-partnership-2016-0|access-date=2019-02-24|work=Cochrane}}</ref> ==== Environmental health and toxicology ==== Systematic reviews are a relatively recent innovation in the field of [[environmental health]] and [[toxicology]]. Although mooted in the mid-2000s, the first full frameworks for conduct of systematic reviews of environmental health evidence were published in 2014 by the US [[National Toxicology Program]]'s Office of Health Assessment and Translation<ref>{{cite journal |vauthors=Rooney AA, Boyles AL, Wolfe MS, Bucher JR, Thayer KA |date=July 2014 |title=Systematic review and evidence integration for literature-based environmental health science assessments |journal=Environmental Health Perspectives |volume=122 |issue=7 |pages=711–718 |doi=10.1289/ehp.1307972 |pmc=4080517 |pmid=24755067|bibcode=2014EnvHP.122..711R }}</ref> and the Navigation Guide at the University of California San Francisco's Program on Reproductive Health and the Environment.<ref>{{cite journal |vauthors=Woodruff TJ, Sutton P |date=October 2014 |title=The Navigation Guide systematic review methodology: a rigorous and transparent method for translating environmental health science into better health outcomes |journal=Environmental Health Perspectives |volume=122 |issue=10 |pages=1007–1014 |doi=10.1289/ehp.1307175 |pmc=4181919 |pmid=24968373|bibcode=2014EnvHP.122.1007W }}</ref> Uptake has since been rapid, with the estimated number of systematic reviews in the field doubling since 2016 and the first consensus recommendations on best practice, as a precursor to a more general standard, being published in 2020.<ref>{{cite journal |display-authors=6 |vauthors=Whaley P, Aiassa E, Beausoleil C, Beronius A, Bilotta G, Boobis A, de Vries R, Hanberg A, Hoffmann S, Hunt N, Kwiatkowski CF, Lam J, Lipworth S, Martin O, Randall N, Rhomberg L, Rooney AA, Schünemann HJ, Wikoff D, Wolffe T, Halsall C |date=October 2020 |title=Recommendations for the conduct of systematic reviews in toxicology and environmental health research (COSTER) |journal=Environment International |volume=143 |pages=105926 |bibcode=2020EnInt.14305926W |doi=10.1016/j.envint.2020.105926 |pmid=32653802 |s2cid=220502683 |doi-access=free |hdl-access=free |hdl=2066/229303}}</ref> === Social, behavioural, and educational === In 1959, social scientist and social work educator [[Barbara Wootton]] published one of the first contemporary systematic reviews of literature on anti-social behavior as part of her work, ''Social Science and Social Pathology''.<ref>{{cite book | vauthors = Gough D, Oliver S, Thomas J |title=An Introduction to Systematic Reviews |date=2017 |publisher=Sage |location=London |page=XIII |edition=2nd}}</ref><ref>{{cite book | vauthors = Oakley A |title=A critical woman : Barbara Wootton, social science and public policy in the twentieth century |date=2011 |publisher=Bloomsbury Academic |location=London |isbn=9781849664707}}</ref> Several organisations use systematic reviews in social, behavioural, and educational areas of evidence-based policy, including the [[National Institute for Health and Care Excellence]] (NICE, UK), [[Social Care Institute for Excellence]] (SCIE, UK), the [[Agency for Healthcare Research and Quality]] (AHRQ, US), the [[World Health Organization]], the International Initiative for Impact Evaluation (3ie), the [[Joanna Briggs Institute]], and the [[Campbell Collaboration]]. The quasi-standard for systematic review in the social sciences is based on the procedures proposed by the Campbell Collaboration, which is one of several groups promoting [[evidence-based policy]] in the [[social science]]s.<ref>{{cite web|title=History of the Campbell Collaboration|url=https://www.campbellcollaboration.org/about-campbell/history.html|access-date=2021-04-15|website=Campbell Collaboration}}</ref> === Others === Some attempts to transfer the procedures from medicine to business research have been made,<ref>{{cite journal|vauthors=Tranfield D, Denyer D, Smart P|year=2003|title=Towards a methodology for developing evidence-informed management knowledge by means of systematic review|journal=British Journal of Management|volume=14|issue=3|pages=207–222|citeseerx=10.1.1.622.895|doi=10.1111/1467-8551.00375}}</ref> including a step-by-step approach,<ref>{{cite journal|vauthors=Durach CF, Kembro J, Wieland A|year=2017|title=A New Paradigm for Systematic Literature Reviews in Supply Chain Management|journal=Journal of Supply Chain Management|volume=53|issue=4|pages=67–85|doi=10.1111/jscm.12145}}</ref><ref>{{Cite journal |last1=Linnenluecke |first1=Martina K |last2=Marrone |first2=Mauricio |last3=Singh |first3=Abhay K |date=May 2020 |title=Conducting systematic literature reviews and bibliometric analyses |url=http://journals.sagepub.com/doi/10.1177/0312896219877678 |journal=[[Australian Journal of Management]] |language=en |volume=45 |issue=2 |pages=175–194 |doi=10.1177/0312896219877678 |issn=0312-8962}}</ref> and developing a standard procedure for conducting systematic literature reviews in business and economics. Systematic reviews are increasingly prevalent in other fields, such as international development research.<ref name="Hagen-Zanker20122">{{cite web| vauthors = Hagen-Zanker J, Duvendack M, Mallett R, Slater R, Carpenter S, Tromme M |date=January 2012|title=Making systematic reviews work for international development research|url=http://www.odi.org.uk/resources/details.asp?id=6260&title=systematic-review-slrc-international-development-research-methods|publisher=Overseas Development Institute}}</ref> Subsequently, several donors (including the UK [[Department for International Development]] (DFID) and [[AusAid]]) are focusing more on testing the appropriateness of systematic reviews in assessing the impacts of development and [[humanitarian intervention]]s.<ref name="Hagen-Zanker20122" /> The Collaboration for Environmental Evidence (CEE) has a journal titled ''Environmental Evidence'', which publishes systematic reviews, review protocols, and systematic maps on the impacts of human activity and the effectiveness of management interventions.<ref>{{cite web|title=Environmental Evidence: Reliable evidence, informed decisions, better environment|url=https://www.environmentalevidence.org/|access-date=2020-07-01|website=www.environmentalevidence.org}}</ref> == Review tools == A 2022 publication identified 24 systematic review tools and ranked them by inclusion of 30 features deemed most important when performing a systematic review in accordance with best practices. The top six software tools (with at least 21/30 key features) are all proprietary paid platforms, typically web-based, and include:<ref>{{cite journal | vauthors = Cowie K, Rahmatullah A, Hardy N, Holub K, Kallmes K | title = Web-Based Software Tools for Systematic Literature Review in Medicine: Systematic Search and Feature Analysis | journal = JMIR | volume = 10 | issue = 5 | pages = e33219 | date = 2022 | pmid = 35499859 | doi = 10.2196/33219 | pmc = 9112080 | doi-access = free }}</ref> * Giotto Compliance * DistillerSR * Nested Knowledge * EPPI-Reviewer Web * LitStream * JBI SUMARI The Cochrane Collaboration provides a handbook for systematic reviewers of interventions which "provides guidance to authors for the preparation of Cochrane Intervention reviews."<ref name="CochraneHandbook2" /> The ''Cochrane Handbook'' also outlines steps for preparing a systematic review<ref name="CochraneHandbook2" /> and forms the basis of two sets of standards for the conduct and reporting of Cochrane Intervention Reviews (MECIR; Methodological Expectations of Cochrane Intervention Reviews).<ref>{{cite web |title=Methodological Expectations of Cochrane Intervention Reviews (MECIR) |url=http://www.editorial-unit.cochrane.org/mecir |access-date=6 October 2014 |publisher=Cochrane}}</ref> It also contains guidance on integrating patient-reported outcomes into reviews. == Limitations == === Out-dated or risk of bias === While systematic reviews are regarded as the strongest form of evidence, a 2003 review of 300 studies found that not all systematic reviews were equally reliable, and that their reporting can be improved by a universally agreed upon set of standards and guidelines.<ref>{{cite journal | vauthors = Moher D, Tetzlaff J, Tricco AC, Sampson M, Altman DG | title = Epidemiology and reporting characteristics of systematic reviews | journal = PLOS Medicine | volume = 4 | issue = 3 | pages = e78 | date = March 2007 | pmid = 17388659 | pmc = 1831728 | doi = 10.1371/journal.pmed.0040078 | doi-access = free }}</ref> A further study by the same group found that of 100 systematic reviews monitored, 7% needed updating at the time of publication, another 4% within a year, and another 11% within 2 years; this figure was higher in rapidly changing fields of medicine, especially cardiovascular medicine.<ref name="pmid176387142">{{cite journal | vauthors = Shojania KG, Sampson M, Ansari MT, Ji J, Doucette S, Moher D | title = How quickly do systematic reviews go out of date? A survival analysis | journal = Annals of Internal Medicine | volume = 147 | issue = 4 | pages = 224–233 | date = August 2007 | pmid = 17638714 | doi = 10.7326/0003-4819-147-4-200708210-00179 | s2cid = 3988259 }}</ref> A 2003 study suggested that extending searches beyond major databases, perhaps into [[grey literature]], would increase the effectiveness of reviews.<ref>{{cite journal | vauthors = Savoie I, Helmer D, Green CJ, Kazanjian A | title = Beyond Medline: reducing bias through extended systematic review search | journal = International Journal of Technology Assessment in Health Care | volume = 19 | issue = 1 | pages = 168–178 | year = 2003 | pmid = 12701949 | doi = 10.1017/S0266462303000163 | s2cid = 42494895 }}</ref> Some authors have highlighted problems with systematic reviews, particularly those conducted by [[Cochrane (organisation)|Cochrane]], noting that published reviews are often biased, out of date, and excessively long.<ref>{{cite journal | vauthors = Roberts I, Ker K, Edwards P, Beecher D, Manno D, Sydenham E | title = The knowledge system underpinning healthcare is not fit for purpose and must change | journal = BMJ | volume = 350 | pages = h2463 | date = June 2015 | pmid = 26041754 | doi = 10.1136/bmj.h2463 | s2cid = 33523612 | url = https://researchonline.lshtm.ac.uk/id/eprint/2210686/1/bmj.h2463.full.pdf }}</ref> Cochrane reviews have been criticized as not being sufficiently critical in the selection of trials and including too many of low quality. They proposed several solutions, including limiting studies in meta-analyses and reviews to [[Clinical trials registry|registered clinical trials]], requiring that original data be made available for statistical checking, paying greater attention to sample size estimates, and eliminating dependence on only published data. Some of these difficulties were noted as early as 1994:{{blockquote|much poor research arises because researchers feel compelled for career reasons to carry out research that they are ill-equipped to perform, and nobody stops them.|author= Altman DG, 1994<ref>{{cite journal | vauthors = Altman DG | title = The scandal of poor medical research | journal = BMJ | volume = 308 | issue = 6924 | pages = 283–284 | date = January 1994 | pmid = 8124111 | pmc = 2539276 | doi = 10.1136/bmj.308.6924.283 }}</ref>|source=}} Methodological limitations of meta-analysis have also been noted.<ref>{{cite journal | vauthors = Shapiro S | title = Meta-analysis/Shmeta-analysis | journal = American Journal of Epidemiology | volume = 140 | issue = 9 | pages = 771–778 | date = November 1994 | pmid = 7977286 | doi = 10.1093/oxfordjournals.aje.a117324 }}</ref> Another concern is that the methods used to conduct a systematic review are sometimes changed once researchers see the available trials they are going to include.<ref>{{cite journal | vauthors = Page MJ, McKenzie JE, Kirkham J, Dwan K, Kramer S, Green S, Forbes A | title = Bias due to selective inclusion and reporting of outcomes and analyses in systematic reviews of randomised trials of healthcare interventions | journal = The Cochrane Database of Systematic Reviews | volume = 2015 | issue = 10 | pages = MR000035 | date = October 2014 | pmid = 25271098 | pmc = 8191366 | doi = 10.1002/14651858.MR000035.pub2 }}</ref> Some websites have described retractions of systematic reviews and published reports of studies included in published systematic reviews.<ref>{{cite web| vauthors = Roberts I |title=Retraction Of Scientific Papers For Fraud Or Bias Is Just The Tip Of The Iceberg|url=http://www.iflscience.com/editors-blog/retraction-scientific-papers-fraud-or-bias-just-tip-iceberg|access-date=29 June 2015|website=IFL Science!|date=12 June 2015 }}</ref><ref>{{cite web| vauthors = Ferguson C |date=2015-04-02|title=Retraction and republication for Lancet Resp Med tracheostomy paper|url=http://retractionwatch.com/2015/04/02/retraction-and-republication-for-lancet-resp-med-tracheostomy-paper/|access-date=29 June 2015|work=Retraction Watch}}</ref><ref>{{cite web| vauthors = Ferguson C |date=2015-03-26|title=BioMed Central retracting 43 papers for fake peer review|url=http://retractionwatch.com/2015/03/26/biomed-central-retracting-43-papers-for-fake-peer-review/|work=Retraction Watch}}</ref> Eligibility criteria that is arbitrary may affect the perceived quality of the review.<ref>{{cite web| author = Flinders University Library |title=Search Smart: Systematic Reviews: Methodology overview|url=https://flinders.libguides.com/c.php?g=220637&p=1460288|access-date=2020-09-16 |website=flinders.libguides.com |language=en }}</ref><ref>{{cite book| vauthors = Pursell E, McCrae N |url= https://www.worldcat.org/oclc/1182880684 |title=How to Perform a Systematic Literature Review: a guide for healthcare researchers, practitioners and students.|date=2020|publisher=Springer Nature|isbn=978-3-030-49672-2|oclc=1182880684}}</ref> === Limited reporting of data from human studies === The [[AllTrials]] campaign report that around half of clinical trials have never reported results and works to improve reporting.<ref>{{cite web | date=2015-08-20|title=Half of all clinical trials have never reported results|url=http://www.alltrials.net/news/half-of-all-trials-unreported/|access-date=2019-03-08|website=AllTrials}}</ref> 'Positive' trials were twice as likely to be published as those with 'negative' results.<ref>{{cite journal | vauthors = Song F, Parekh S, Hooper L, Loke YK, Ryder J, Sutton AJ, Hing C, Kwok CS, Pang C, Harvey I | display-authors = 6 | title = Dissemination and publication of research findings: an updated review of related biases | journal = Health Technology Assessment | volume = 14 | issue = 8 | pages = iii, ix-xi, 1–193 | date = February 2010 | pmid = 20181324 | doi = 10.3310/hta14080 | doi-access = free }}</ref> As of 2016, it is legal for-profit companies to conduct clinical trials and not publish the results.<ref name="Iacobucci i59552">{{cite journal | vauthors = Iacobucci G | title = Nearly half of all trials run by major sponsors in past decade are unpublished | journal = BMJ | volume = 355 | pages = i5955 | date = November 2016 | pmid = 27815253 | doi = 10.1136/bmj.i5955 | s2cid = 43604202 }}</ref> For example, in the past 10 years, 8.7 million patients have taken part in trials that have not published results.<ref name="Iacobucci i59552" /> These factors mean that it is likely there is a significant publication bias, with only 'positive' or perceived favourable results being published. A recent systematic review of industry sponsorship and research outcomes concluded that "sponsorship of drug and device studies by the manufacturing company leads to more favorable efficacy results and conclusions than sponsorship by other sources" and that the existence of an industry bias that cannot be explained by standard 'risk of bias' assessments.<ref>{{cite journal | vauthors = Lundh A, Lexchin J, Mintzes B, Schroll JB, Bero L | title = Industry sponsorship and research outcome | journal = The Cochrane Database of Systematic Reviews | volume = 2017 | issue = 2 | pages = MR000033 | date = February 2017 | pmid = 28207928 | pmc = 8132492 | doi = 10.1002/14651858.MR000033.pub3 | collaboration = Cochrane Methodology Review Group }}</ref> === Poor compliance with review reporting guidelines === The rapid growth of systematic reviews in recent years has been accompanied by the attendant issue of poor compliance with guidelines, particularly in areas such as declaration of registered study protocols, funding source declaration, risk of bias data, issues resulting from data abstraction, and description of clear study objectives.<ref>{{cite journal | vauthors = Pidgeon TE, Wellstead G, Sagoo H, Jafree DJ, Fowler AJ, Agha RA | title = An assessment of the compliance of systematic review articles published in craniofacial surgery with the PRISMA statement guidelines: A systematic review | journal = Journal of Cranio-Maxillo-Facial Surgery | volume = 44 | issue = 10 | pages = 1522–1530 | date = October 2016 | pmid = 27575881 | doi = 10.1016/j.jcms.2016.07.018 }}</ref><ref>{{cite journal | vauthors = Lee SY, Sagoo H, Whitehurst K, Wellstead G, Fowler AJ, Agha RA, Orgill D | title = Compliance of Systematic Reviews in Plastic Surgery With the PRISMA Statement | journal = JAMA Facial Plastic Surgery | volume = 18 | issue = 2 | pages = 101–105 | date = 2016-03-01 | pmid = 26719993 | doi = 10.1001/jamafacial.2015.1726 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Akhigbe T, Zolnourian A, Bulters D | title = Compliance of systematic reviews articles in brain arteriovenous malformation with PRISMA statement guidelines: Review of literature | journal = Journal of Clinical Neuroscience | volume = 39 | pages = 45–48 | date = May 2017 | pmid = 28246008 | doi = 10.1016/j.jocn.2017.02.016 | s2cid = 27738264 }}</ref><ref>{{cite journal | vauthors = Lee SY, Sagoo H, Farwana R, Whitehurst K, Fowler A, Agha R | title = Compliance of systematic reviews in ophthalmology with the PRISMA statement | journal = BMC Medical Research Methodology | volume = 17 | issue = 1 | pages = 178 | date = December 2017 | pmid = 29281981 | pmc = 5745614 | doi = 10.1186/s12874-017-0450-1 | doi-access = free }}</ref><ref>{{cite journal | vauthors = E JY, Saldanha IJ, Canner J, Schmid CH, Le JT, Li T | title = Adjudication rather than experience of data abstraction matters more in reducing errors in abstracting data in systematic reviews | journal = Research Synthesis Methods | volume = 11 | issue = 3 | pages = 354–362 | date = May 2020 | pmid = 31955502 | doi = 10.1002/jrsm.1396 | s2cid = 210829764 }}</ref> A host of studies have identified weaknesses in the rigour and reproducibility of search strategies in systematic reviews.<ref>{{cite journal | vauthors = Koffel JB, Rethlefsen ML | title = Reproducibility of Search Strategies Is Poor in Systematic Reviews Published in High-Impact Pediatrics, Cardiology and Surgery Journals: A Cross-Sectional Study | journal = PLOS ONE | volume = 11 | issue = 9 | pages = e0163309 | date = 2016-09-26 | pmid = 27669416 | pmc = 5036875 | doi = 10.1371/journal.pone.0163309 | veditors = Thombs BD | doi-access = free | bibcode = 2016PLoSO..1163309K }}</ref><ref>{{cite journal | vauthors = Yoshii A, Plaut DA, McGraw KA, Anderson MJ, Wellik KE | title = Analysis of the reporting of search strategies in Cochrane systematic reviews | journal = Journal of the Medical Library Association | volume = 97 | issue = 1 | pages = 21–29 | date = January 2009 | pmid = 19158999 | pmc = 2605027 | doi = 10.3163/1536-5050.97.1.004 }}</ref><ref>{{cite journal | vauthors = Toews LC | title = Compliance of systematic reviews in veterinary journals with Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) literature search reporting guidelines | journal = Journal of the Medical Library Association | volume = 105 | issue = 3 | pages = 233–239 | date = July 2017 | pmid = 28670210 | pmc = 5490700 | doi = 10.5195/jmla.2017.246 }}</ref><ref>{{cite journal | vauthors = Mullins MM, DeLuca JB, Crepaz N, Lyles CM | title = Reporting quality of search methods in systematic reviews of HIV behavioral interventions (2000-2010): are the searches clearly explained, systematic and reproducible? | journal = Research Synthesis Methods | volume = 5 | issue = 2 | pages = 116–130 | date = June 2014 | pmid = 26052651 | pmc = 5861495 | doi = 10.1002/jrsm.1098 }}</ref><ref>{{cite journal | vauthors = Briscoe S | title = A review of the reporting of web searching to identify studies for Cochrane systematic reviews | journal = Research Synthesis Methods | volume = 9 | issue = 1 | pages = 89–99 | date = March 2018 | pmid = 29065246 | doi = 10.1002/jrsm.1275 | s2cid = 206155997 }}</ref><ref>{{cite journal | vauthors = Golder S, Loke Y, McIntosh HM | title = Poor reporting and inadequate searches were apparent in systematic reviews of adverse effects | journal = Journal of Clinical Epidemiology | volume = 61 | issue = 5 | pages = 440–448 | date = May 2008 | pmid = 18394536 | doi = 10.1016/j.jclinepi.2007.06.005 }}</ref> To remedy this issue, a new PRISMA guideline extension called PRISMA-S is being developed.<ref>{{cite journal | vauthors = Rethlefsen ML, Kirtley S, Waffenschmidt S, Ayala AP, Moher D, Page MJ, Koffel JB | title = PRISMA-S: an extension to the PRISMA statement for reporting literature searches in systematic reviews | journal = Journal of the Medical Library Association | volume = 109 | issue = 2 | pages = 174–200 | date = April 2021 | pmid = 34285662 | doi = 10.17605/OSF.IO/YGN9W | pmc = 8270366 }}</ref> Furthermore, tools and checklists for peer-reviewing search strategies have been created, such as the Peer Review of Electronic Search Strategies (PRESS) guidelines.<ref>{{cite journal | vauthors = McGowan J, Sampson M, Salzwedel DM, Cogo E, Foerster V, Lefebvre C | title = PRESS Peer Review of Electronic Search Strategies: 2015 Guideline Statement | journal = Journal of Clinical Epidemiology | volume = 75 | pages = 40–46 | date = July 2016 | pmid = 27005575 | doi = 10.1016/j.jclinepi.2016.01.021 | doi-access = free }}</ref> A key challenge for using systematic reviews in clinical practice and healthcare policy is assessing the quality of a given review. Consequently, a range of appraisal tools to evaluate systematic reviews have been designed. The two most popular measurement instruments and scoring tools for systematic review quality assessment are AMSTAR 2 (a measurement tool to assess the methodological quality of systematic reviews)<ref>{{cite journal | vauthors = Shea BJ, Reeves BC, Wells G, Thuku M, Hamel C, Moran J, Moher D, Tugwell P, Welch V, Kristjansson E, Henry DA | display-authors = 6 | title = AMSTAR 2: a critical appraisal tool for systematic reviews that include randomised or non-randomised studies of healthcare interventions, or both | journal = BMJ | volume = 358 | pages = j4008 | date = September 2017 | pmid = 28935701 | pmc = 5833365 | doi = 10.1136/bmj.j4008 }}</ref><ref>{{cite journal | vauthors = Shea BJ, Grimshaw JM, Wells GA, Boers M, Andersson N, Hamel C, Porter AC, Tugwell P, Moher D, Bouter LM | display-authors = 6 | title = Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews | journal = BMC Medical Research Methodology | volume = 7 | issue = 1 | pages = 10 | date = February 2007 | pmid = 17302989 | pmc = 1810543 | doi = 10.1186/1471-2288-7-10 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Shea BJ, Hamel C, Wells GA, Bouter LM, Kristjansson E, Grimshaw J, Henry DA, Boers M | display-authors = 6 | title = AMSTAR is a reliable and valid measurement tool to assess the methodological quality of systematic reviews | journal = Journal of Clinical Epidemiology | volume = 62 | issue = 10 | pages = 1013–1020 | date = October 2009 | pmid = 19230606 | doi = 10.1016/j.jclinepi.2008.10.009 | s2cid = 5935312 | url = https://research.vu.nl/en/publications/ee9eadc9-eb7d-419c-a869-575260a0b800 }}</ref> and ROBIS (Risk Of Bias In Systematic reviews); however, these are not appropriate for all systematic review types.<ref>{{cite journal | vauthors = Whiting P, Savović J, Higgins JP, Caldwell DM, Reeves BC, Shea B, Davies P, Kleijnen J, Churchill R | display-authors = 6 | title = ROBIS: A new tool to assess risk of bias in systematic reviews was developed | journal = Journal of Clinical Epidemiology | volume = 69 | pages = 225–234 | date = January 2016 | pmid = 26092286 | pmc = 4687950 | doi = 10.1016/j.jclinepi.2015.06.005 }}</ref> Some recent peer-reviewed articles have carried out comparisons between AMSTAR 2 and ROBIS tools.<ref>{{Cite journal |last1=Perry |first1=R. |last2=Whitmarsh |first2=A. |last3=Leach |first3=V. |last4=Davies |first4=P. |date=2021-10-25 |title=A comparison of two assessment tools used in overviews of systematic reviews: ROBIS versus AMSTAR-2 |journal=Systematic Reviews |volume=10 |issue=1 |pages=273 |doi=10.1186/s13643-021-01819-x |doi-access=free |issn=2046-4053 |pmc=8543959 |pmid=34696810}}</ref><ref>{{Cite journal |last1=Pieper |first1=Dawid |last2=Puljak |first2=Livia |last3=González-Lorenzo |first3=Marien |last4=Minozzi |first4=Silvia |date=April 2019 |title=Minor differences were found between AMSTAR 2 and ROBIS in the assessment of systematic reviews including both randomized and nonrandomized studies |url=https://pubmed.ncbi.nlm.nih.gov/30543911/ |journal=Journal of Clinical Epidemiology |volume=108 |pages=26–33 |doi=10.1016/j.jclinepi.2018.12.004 |issn=1878-5921 |pmid=30543911}}</ref> == History == The first publication that is now recognized as equivalent to a modern systematic review was a 1753 paper by [[James Lind]], which reviewed all of the previous publications about [[scurvy]].<ref name=":9">{{Cite journal |last1=Clarke |first1=Mike |last2=Chalmers |first2=Iain |date=August 2018 |title=Reflections on the history of systematic reviews |journal=BMJ Evidence-Based Medicine |language=en |volume=23 |issue=4 |pages=121–122 |doi=10.1136/bmjebm-2018-110968 |pmid=29921711 |s2cid=49311760 |issn=2515-446X|doi-access=free }}</ref> Systematic reviews appeared only sporadically until the 1980s, and became common after 2000.<ref name=":9" /> More than 10,000 systematic reviews are published each year.<ref name=":9" /> === History in medicine === A 1904 ''[[The BMJ|British Medical Journal]]'' paper by [[Karl Pearson]] collated data from several studies in the UK, India and South Africa of [[Typhoid vaccine|typhoid inoculation]]. He used a meta-analytic approach to aggregate the outcomes of multiple clinical studies.<ref>{{cite journal |author= |date=November 1904 |title=Report on Certain Enteric Fever Inoculation Statistics |journal=British Medical Journal |publisher=British Medical Journal Publishing Group |volume=2 |issue=2288 |pages=1243–1246 |doi=10.1136/bmj.2.2288.1243 |pmc=2355479 |pmid=20761760 |s2cid=30331745}}</ref> In 1972, Archie Cochrane wrote: "It is surely a great criticism of our profession that we have not organised a critical summary, by specialty or subspecialty, adapted periodically, of all relevant randomised controlled trials".<ref name=":7">{{cite web |title=1.1.2 A brief history of Cochrane |url=https://community.cochrane.org/handbook-sri/chapter-1-introduction/11-cochrane/112-brief-history-cochrane |archive-url=https://web.archive.org/web/20190117070242/https://community.cochrane.org/handbook-sri/chapter-1-introduction/11-cochrane/112-brief-history-cochrane |archive-date=2019-01-17 |access-date=2019-02-24 |website=community.cochrane.org |language=en}}</ref> Critical appraisal and synthesis of research findings in a systematic way emerged in 1975 under the term 'meta analysis'.<ref>{{cite book |url=https://catalogue.nla.gov.au/Record/5363514 |title=Meta-Analysis of Research on the Relationship of Class-Size and Achievement. The Class Size and Instruction Project |vauthors=Glass GV, Smith ML |collaboration=Far West Lab. for Educational Research and Development, San Francisco, CA |date=1978 |publisher=Distributed by ERIC Clearinghouse |location=Washington, D.C.]}}</ref><ref>{{cite web |title=History of Systematic Reviews |url=https://eppi.ioe.ac.uk/cms/Resources/EvidenceInformedPolicyandPractice/HistoryofSystematicReviews/tabid/68/Default.aspx |access-date=2019-02-24 |work=Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-Centre)}}</ref> Early syntheses were conducted in broad areas of public policy and social interventions, with systematic research synthesis applied to medicine and health.<ref>{{cite journal |vauthors=Lau J, Antman EM, Jimenez-Silva J, Kupelnick B, Mosteller F, Chalmers TC |date=July 1992 |title=Cumulative meta-analysis of therapeutic trials for myocardial infarction |journal=The New England Journal of Medicine |volume=327 |issue=4 |pages=248–254 |doi=10.1056/NEJM199207233270406 |pmid=1614465 |doi-access=free}}</ref> Inspired by his own personal experiences as a senior medical officer in prisoner of war camps, [[Archie Cochrane]] worked to improve the scientific method in medical evidence.<ref>{{cite book |url=https://www.worldcat.org/oclc/741462 |title=Effectiveness and efficiency: random reflections on health services |vauthors=Cochrane AL |date=1972 |publisher=Nuffield Provincial Hospitals Trust |isbn=0-900574-17-8 |location=[London] |oclc=741462 |archive-url=https://web.archive.org/web/20200916053459/https://www.nuffieldtrust.org.uk/files/2017-01/effectiveness-and-efficiency-web-final.pdf |archive-date=2020-09-16}}</ref> His call for the increased use of randomised controlled trials and systematic reviews led to the creation of The Cochrane Collaboration,<ref>{{cite journal |vauthors=Shah HM, Chung KC |date=September 2009 |title=Archie Cochrane and his vision for evidence-based medicine |journal=Plastic and Reconstructive Surgery |volume=124 |issue=3 |pages=982–988 |doi=10.1097/PRS.0b013e3181b03928 |pmc=2746659 |pmid=19730323}}</ref> which was founded in 1993 and named after him, building on the work by [[Iain Chalmers]] and colleagues in the area of pregnancy and childbirth.<ref>{{cite book |url=https://www.worldcat.org/oclc/778837501 |title=Testing treatments : better research for better healthcare |vauthors=Evans I, Thornton H, Chalmers I, Glasziou P |date=2011 |publisher=Pinter & Martin |isbn=978-1-905177-48-6 |edition=Second |location=London |oclc=778837501}}</ref><ref name=":7" /> == See also == * [[Critical appraisal]] * [[Further research is needed]] * [[Systematic searching]] * [[Horizon scanning]] * [[Literature review]] * [[Living review]] * [[Meta-analysis]] * [[Metascience]] * [[Peer review]] * [[Review journal]] * [[Generalized model aggregation|Generalized model aggregation (GMA)]] * [[Umbrella review]] == References == {{Academic peer reviewed|Q99440266|doi-access=free}} [[wikidata:Q98550843|STARDIT report]] [[Wikidata:Q101116128|Q101116128]]. {{Reflist}} == External links == {{Commons category}} {{Library resources box |by=no |onlinebooks=no |others=no |about=yes |label=systematic review }} * [http://www.systematicreviewtools.com Systematic Review Tools] — Search and list of systematic review software tools * [http://www.cochrane.org/ Cochrane Collaboration] * MeSH: [https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=mesh&list_uids=68012196&dopt=Full Review Literature]—articles about the review process * MeSH: [https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=mesh&list_uids=68016454&dopt=Full Review [Publication Type&#93;] - limit search results to reviews * [http://www.prisma-statement.org/ Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement] {{Webarchive|url=https://web.archive.org/web/20110727021816/http://www.prisma-statement.org/ |date=27 July 2011 }}, "an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses" * [http://www.equator-network.org/reporting-guidelines/prisma-scr/ PRISMA Extension for Scoping Reviews (PRISMA-ScR): Checklist and explanation] * [https://cccrg.cochrane.org/animated-storyboard-what-are-systematic-reviews Animated Storyboard: What Are Systematic Reviews?] - Cochrane Consumers and Communication Group * [https://sysrev.com/ Sysrev] - a free platform with open access systematic reviews. * [[doi:10.1186/s40900-022-00363-9|STARDIT]] - an open access data-sharing system to standardise the way that information about initiatives is reported. {{Medical research studies}} {{DEFAULTSORT:Systematic Review}} [[Category:Systematic review| ]] [[Category:Review journals|*]] [[Category:Evidence-based practices]] [[Category:Information science]] [[Category:Meta-analysis]] [[Category:Nursing research]] </textarea><div class="templatesUsed"><div class="mw-templatesUsedExplanation"><p><span id="templatesused">Pages transcluded 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