PROSPERO International prospective register of systematic reviews

Background: the need for registration Systematic reviews usually provide the evidence base upon which health and social care decisions are made so they should be robust and free from bias There is concern about publication and selective outcome reporting biases associated with systematic reviews Unplanned duplication of reviews is a waste of resource No open register for review protocols (Cochrane and Campbell Collaboration protocol registration limited to their own organisations) PRISMA 2009 Checklist: asks for protocol and registration details References: Moher D, Tetzlaff J, Tricco AC, Sampson M, Altman DG. Epidemiology and reporting characteristics of systematic reviews. PLoS Med 2007; 4: e78. PLoS Medicine Editors. Many reviews are systematic but some are more transparent and completely reported than others. PLoS Med 2007; 4: e147. Silagy CA, Middleton P, Hopewell S. Publishing protocols of systematic reviews: comparing what was done to what was planned. JAMA 2002; 287: 2831–34. Kirkham JJ, Altman DG, Williamson PR. Bias due to changes in specified outcomes during the systematic review process. PLoS ONE 2010; 5: e9810 Kirkham JJ, Dwan KM, Altman DG, et al. The impact of outcome reporting bias in randomised controlled trials on a cohort of systematic reviews. BMJ 2010; 340:c365. Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gøtzsche PC, Ioannidis JPA, Clarke M, Devereaux PJ, Kleijnen J, Moher D: The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Med 2009, 6(7):e1000100. Moher D, Tetzlaff J, Altman DG, The PRISMA Group Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. In: PLoS Med. vol. 6; 2009: e1000097.

Taking the initiative Following publication of the PRISMA statement CRD began to receive unsolicited requests to register systematic reviews CRD has an established IT platform and infrastructure for the DARE, NHS EED and HTA databases Set up an international advisory group Carried out an international consultation to establish a minimum dataset and raise awareness Membership of the advisory group: Alison Booth, Centre for Reviews and Dissemination, University of York, York, UK Lesley Stewart, Centre for Reviews and Dissemination, University of York, York, UK Mike Clarke, Centre for Public Health, Queen’s University Belfast, Belfast, UK (formerly Director of UK Cochrane Centre) Gordon Dooley, Metaxis, Oxford, UK Davina Ghersi, Research Translation Branch, National Health & Medical Research Council, Canberra, Australia (formerly Coordinator of the WHO ICTRP) David Moher, Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada; Department of Epidemiology and Community Medicine, faculty of Medicine, University of Ottawa, Ottawa, Canada Mark Petticrew, Department of Social and Environmental Health Research, London School of Hygiene and Tropical Medicine, London, UK Details of the Delphi consultation exercise have been published: Booth A, Clarke M, Ghersi D, Moher D, Petticrew M, et al. (2011) Establishing a Minimum Dataset for Prospective Registration of Systematic Reviews: An International Consultation. PLoS ONE 6(11): e27319. doi:10.1371/journal.pone.0027319 Http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0027319 Booth A, Clarke M, Dooley G, Ghersi D, Moher D, Petticrew M, Stewart L. The nuts and bolts of PROSPERO: an international prospective register of systematic reviews. (submitted to Systematic Reivews; for publication early 2012)

Registration minimum dataset 22 required fields: Review design Administrative Review question/objective Condition/domain studied Search details Participants/population Intervention/exposure Comparator/control Study types Primary outcomes Secondary outcomes Risk of bias (quality) assessment Strategy for data synthesis Planned subgroup analyses Review title Named contact(s) Contact e-mail Organisational affiliation Funding source/sponsors Conflict of interests Anticipated or actual start date Stage of review† Anticipated completion date Review status† † these fields are updated as the review progresses Result of the consultation = minimum dataset 22 required fields – minimum to achieve aims of the register – registration form developed to make registration as straight forward as possible – level of information required is sufficient to allow others to see what was planned and allow comparison with what is reported on completion. These are the fields that have to be completed before a form can be submitted.

Registration dataset 18 optional fields: Administrative Review design Contact postal address Contact phone number Review team members & affiliations Collaborators Other registration details Organisational reference number Language Country Key words Existing review by same authors Any other information ‡ Type of review URL to search strategy URL to full protocol‡ Context Data extraction methods Dissemination plan Link to final report/publication ‡ (added over time) ‡ Fields included in response to Delphi comments

PROSPERO: International prospective register of systematic reviews Web based Free to register Free to search Users create and update their own records Minimum data set required Record content is the responsibility of review lead Administrators check for “sense” not peer review A public audit trail of amendments is maintained PROSPERO was launched on 22 Feb 2011

Eligibility for inclusion in PROSPERO Systematic reviews of the effects of interventions and strategies to prevent, diagnose, treat, and monitor health conditions, for which there is a health related outcome Exclusions: Reviews of reviews, Scoping reviews, Reviews of methods, Reviews of animal studies Completed reviews are not accepted Registration should take place once the systematic review protocol is finalised, but ideally before screening studies for inclusion begins Working on automatic upload of Cochrane protocols, so they should not be registered individually The long term aim is to have broad inclusion criteria for PROSPERO, such that any systematic review that has a health related outcome will be eligible. However, to achieve this aim, a stepped approach is being taken. To begin with the focus for inclusion is on … Scoping reviews and reviews of reviews are not being included initially, but this decision will be re-considered in the future. The inclusion of Cochrane review protocols is desirable to ensure a comprehensive overview of ongoing systematic reviews. To minimise additional work for Cochrane reviewers an electronic mechanism for their automatic upload from the Cochrane Library is being developed. Timing: As registration requires the completion of a minimum dataset, registration can only take place after key issues have been considered, preferably through preparation of a protocol. For the register to achieve its aim of providing transparency and helping identify potential bias, registration should ideally take place before formal screening against inclusion criteria has begun, this being an early point at which bias could be introduced. However, the systematic review process is iterative by nature and some experimentation with searching is likely to be essential in developing the review. It also has to be recognised that researchers are often aware of some of the potentially eligible studies, and have an opinion on whether they are likely to include or exclude these, before they start formal screening.   Registering a review too soon might lead to multiple amendments to records as the protocol and the plans for the review are finalised; register later and the aim of publishing methods a priori could be missed. A practical approach to the timing of registration has been taken, initially. Registrants are asked to indicate the stage of progress of the review at the time of initial registration, and at any subsequent revisions, by ticking the boxes for the relevant stage from a list, with the option of adding further information in a free text box. All records and revisions are automatically dated when published to the register. In recognition of reviews already underway during PROSPERO’s first year, systematic reviews at any stage before the point of completing data extraction are being considered for inclusion. The issue of timing of registration is to be reviewed as part of a planned evaluation of the register.

The story so far… PROSPERO opened for registration 22 February 2011 By November 2011: Registered reviews being undertaken in 27 different countries 227 registrations published : 217 are ongoing reviews 8 are completed but not yet published 2 are completed and published 55 submissions rejected – almost all because they were too far advanced or completed on first submission

Current and future developments Support from organisations such as Cochrane and Campbell Collaborations, Joanna Briggs Institute, G-I-N, INAHTA Support from PLoS journals, BMJ and the new BMC journal Systematic Reviews Establishing mechanisms with commissioning and funding organisations to facilitate grant holder uptake and compliance National Institute for Health Research (UK) Canadian Institutes of Health Research Currently promoting registration phase of development and planning promotion of search facility Evaluation after one year of operation planned

Visitors to the PROSPERO website Between the launch on 22 Feb 2011 and 22 Nov 2011 the PROSPERO site had over 10,000 visitors from 104 different identifiable countries or territories

www.crd.york.ac.uk/PROSPERO