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

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

Registration minimum dataset 22 required fields: Administrative Review title Named contact(s) Contact 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 Review design 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

Registration dataset 18 optional fields: Administrative 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 ‡ Review design 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

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 story so far… PROSPERO opened for registration 22 February 2011 By February 2012: Registered reviews being undertaken in 33 different countries 359 registrations published: 339 are ongoing reviews 15 are completed but not yet published 3 are completed and published 2 are updates of existing reviews 89 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, BMJ Open 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 Feb 2012 the PROSPERO site had nearly 14,000 visitors from 104 different identifiable countries or territories