PROSPERO is the international prospective register of systematic reviews maintained by the Center for Reviews and Dissemination (CRD) at the University of York. The platform relaunched on February 24, 2025, with a rebuilt infrastructure and several process changes that affect how reviews are registered, approved, and published. The changes are significant enough that researchers who registered reviews before February 2025 and those using PROSPERO for the first time will encounter a materially different system.
The two changes that affect research teams most immediately are the mandatory all-author approval requirement and automated processing for qualifying reviews. Under the approval requirement, a record does not go live until every named co-author individually approves by email. Automated processing means many registrations are now published within 24 hours rather than the previous five to ten working day manual screening timeline.
The all-author approval requirement and the LATITUDES dropdown are the two steps that delay most 2025 PROSPERO registrations; ScribeLab Writer's protocol and registration service manages both, with the full February 2025 workflow documented and a 24-hour quote.
Quick Answer:
PROSPERO relaunched on February 24, 2025 with three major changes: (1) all named co-authors must individually approve the registration by email before the record publishes, which can delay registration if co-authors are slow to respond; (2) a similar-reviews detection feature automatically flags existing registrations with overlapping scope during submission; and (3) qualifying reviews are now processed automatically without manual CRD screening, with some records publishing within 24 hours. The new platform also introduced restricted dropdown menus for funding sources and risk-of-bias tools (the latter drawn from the LATITUDES list). Records registered before February 24, 2025, were not subject to the all-author approval requirement. The rate of new registrations reached approximately 200 to 300 per day as of 2025.
Why PROSPERO Registration Matters
PROSPERO registration is a core component of systematic review transparency and a publication requirement at an increasing number of high-impact journals. Registration before searching begins serves three functions. First, it creates a publicly accessible, time-stamped record of the intended methodology, protecting against duplicate reviews and outcome-reporting bias. Second, it demonstrates prospective planning to peer reviewers, strengthening the methodological credibility of the review. Third, it is a specific requirement for Cochrane reviews and many journal author guidelines, including the BMJ, JAMA, and The Lancet.
Registration after the search has begun or after data extraction is underway is not recommended and is not considered prospective. PROSPERO allows retrospective registration but requires the date of the search to be recorded accurately. Peer reviewers at methods-focused journals note whether the search preceded or followed PROSPERO registration. A post-search registration invites scrutiny of whether the protocol was shaped by the available evidence.
Under the updated 2025 platform, the registration timeline has new dependencies that teams must account for before beginning their search. Specifically, the all-author approval requirement means that registration is not complete until every co-author has responded to an automated approval email. A research team that begins searching while waiting for a co-author to approve the PROSPERO record technically begins their search before registration is complete.
What Changed on February 24, 2025
The February 2025 relaunch updated four aspects of the PROSPERO platform: the approval workflow, the duplicate detection process, the processing model, and several form fields.
Table 1: PROSPERO Platform Changes: Before and After February 24, 2025
Feature | Before February 24, 2025 | After February 24, 2025 | Action Required |
|---|---|---|---|
Author approval | Corresponding author submits. Record published after CRD screening. Co-authors not individually notified. | All named co-authors must individually approve via email before the record publishes. | Notify all co-authors before submitting. Confirm email addresses are correct. Allow extra time for slow responders. |
Duplicate detection | No automated duplicate detection. CRD screened manually. | Automated similar-reviews detection during submission. Submitter must acknowledge flags and explain how their review is distinct. | Search PROSPERO for similar reviews before submission. Prepare a brief explanation of what your review adds if a flag is triggered. |
Processing timeline | Manual CRD screening. Typically, 5–10 working days for most submissions. | Automated processing for qualifying submissions. Some records are published within 24 hours. Manual processing still applies where the criteria are not met. | Do not rely on automated processing. Build a 2-week buffer between submission and planned search date. |
Funding source field | Free-text entry. | Restricted dropdown with defined categories. Free-text alternative available for some categories. | Select the closest matching dropdown option. Use free-text only when no listed option applies. |
Risk-of-bias tool field | Free-text entry. | Dropdown from the LATITUDES taxonomy. Free-text box for tools not on the list. | Select RoB 2 for RCTs, ROBINS-I V2 for non-randomized studies, QUADAS-2 for DTA. Select all tools that apply. |
Editing a pending record | Edits are possible before the CRD publication decision. | Use "Cancel this submission" to return to the draft. Content is retained. All co-authors must re-approve after resubmission. | Ensure all information is accurate and all co-authors are notified before initial submission to avoid the cancel-resubmit cycle. |
All-author approval. The most significant operational change is the requirement that a PROSPERO record does not publish until all named review team members have approved the submission and confirmed that the content is accurate and that they consent to being listed. Approval is triggered by an automated email sent to each co-author at the time of submission. Each co-author clicks a link in the email to confirm their approval. The record does not go live until all approvals are received.
Similar reviews detection. The new platform automatically searches existing PROSPERO records during submission and flags any records with overlapping scope, population, or intervention. This feature is designed to reduce what the PROSPERO team has described as "zombie reviews": duplicate registrations for reviews that closely mirror existing registered or published reviews (Booth et al., 2017). When the system flags a similar review, the submitter is required to acknowledge the flag and explain why their review is sufficiently distinct before proceeding.
Automated processing. Under the previous PROSPERO system, submissions were screened manually by CRD staff, and the process took five to ten working days. The updated platform introduced automated processing for qualifying submissions, with eligible registrations publishing automatically without manual review. A 2025 commentary in the Journal of Psychiatry Spectrum reported that one protocol was registered within 24 hours of submission under the new system.
Updated form fields. The new platform introduced restricted dropdown menus for two categories that previously allowed free-text entry. Funding sources now require selection from a defined list rather than free-text entry. Risk-of-bias and quality assessment tools now require selection from the LATITUDES list, a curated taxonomy of critical appraisal tools, with a free-text box available for tools not on the list.
The All-Author Approval Requirement: What Research Teams Need to Know
The all-author approval requirement is the most operationally demanding of the 2025 changes. Research teams with more than two or three co-authors, or those working with international collaborators across time zones, need to build this approval step into their registration timeline.
How approval works. When the corresponding author submits the draft registration, PROSPERO sends an automated approval email to each listed co-author. Each email contains a unique link. The co-author clicks the link and confirms their approval. The record does not publish until all links have been clicked. There is no publicly stated deadline for co-author approval under the updated system.
What happens if a co-author does not respond? If a co-author fails to respond to the approval email, the submission remains in a pending state. The corresponding author should contact unresponsive co-authors directly and ask them to check their email, including spam folders, for the PROSPERO approval request. If the email was not received, the submission can be canceled, the co-author's email address can be corrected, and the record can be resubmitted, which triggers a new approval email to all co-authors.
Canceling a pending submission. Under the updated platform, a submitted-but-unpublished record can be returned to draft status using the "Cancel this submission" option. The content of the record is retained in draft form. All co-authors must re-approve after any resubmission. Researchers should therefore ensure all information is accurate and all co-authors have been notified before submitting, to avoid the cycle of cancel-revise-resubmit-reapprove.
Records submitted before February 24, 2025. Records that were submitted and in the CRD screening queue before the platform relaunch were not subject to the all-author approval requirement. Some fields in these older records may be incomplete under the new mandatory field structure, as indicated by a progress bar showing completion percentage per section. These records are valid registrations, and their registration date is not affected by the relaunch.
The Similar-Reviews Detection Feature
The similar-reviews feature addresses duplicate registrations. This had become a significant problem as PROSPERO's registration volume grew to approximately 200 to 300 new records per day (Journal of Psychiatry Spectrum, 2025).
When the system flags a similar existing review, the submitting researcher faces one of three scenarios.
The existing review is identical. If the flagged record is a completed or ongoing review on the same population, intervention, comparison, and outcome as the submission, the research team should reconsider whether their review adds sufficient methodological or scope distinction to justify registration. Registering a duplicate review wastes reviewer and journal resources and is unlikely to be accepted for publication at a high-impact journal that checks PROSPERO records during peer review.
The existing review is similar but distinct. If the flagged record covers overlapping but not identical scopes, the submitter should articulate the distinction clearly in the PROSPERO form. The distinction may be a different population subgroup, a different comparison arm, a longer date range, a different geographic scope, a different study design inclusion criterion, or a methodological innovation such as an individual patient data approach. The explanation should be specific and verifiable, not vague assertions of differentiation.
The existing review is completed. If a similar flagged review was published more than three years ago and the evidence base has expanded since publication, an updated review or a new review that extends the evidence period may be justifiable. The submission should acknowledge the prior review explicitly and describe what the new registration adds.
Need a PROSPERO-compliant protocol written and registered under the 2025 platform requirements? |
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The all-author approval workflow, the LATITUDES tool selection, and the similar-reviews detection step add coordination requirements that are easy to underestimate on a first PROSPERO registration. ScribeLab Writer's protocol and registration service develops PROSPERO-compliant protocols from PICO formulation through to a published record, managing the full 2025 approval workflow on your behalf. A PhD methodologist will respond within 24 hours. |
Automated Processing: What Qualifies
The new automated processing track applies to submissions that meet PROSPERO's completeness and eligibility criteria without requiring manual review by CRD staff. The specific eligibility criteria for automated processing are determined by PROSPERO's internal quality thresholds and are not publicly listed in full detail.
Reviews that qualify for automated processing tend to have complete information in all mandatory fields, a clearly defined PICO, and a named risk-of-bias tool from the LATITUDES dropdown. They also require a named funding source from the defined list and no content that requires human editorial judgment to assess eligibility. Reviews involving unusual review types, non-standard databases, or complex eligibility conditions may still require manual CRD processing.
Researchers should not assume automated processing will apply to their submission. If a fast registration timeline is needed, begin the process and coordinate all author approvals well before the intended search date. This allows time for manual processing if automated processing does not apply.
Changes to the PROSPERO Registration Form
Beyond the workflow changes, the updated form introduced several field-level changes that affect how researchers complete a registration.
Funding source dropdown. The free-text funding field has been replaced with a dropdown menu. Common funding categories are included. Researchers should select the most accurate available option. If no option fits, a free-text alternative is available for some categories.
Risk-of-bias and quality tool dropdown. The appraisal tool field now requires selection from the LATITUDES list, a taxonomy of critical appraisal tools maintained to support evidence synthesis methodology research. Tools on the LATITUDES list include RoB 2, ROBINS-I (select V2 for the current version), QUADAS-2, AMSTAR 2, GRADE, NOS, CASP checklists, and others. A free-text field remains available for tools not on the LATITUDES list.
Co-author email fields. The registration form now requires email addresses for all listed co-authors, as these are used to send the approval notifications. Errors in co-author email addresses will prevent the approval emails from reaching the intended recipients.
Registering a Systematic Review Under the New System: A Practical Checklist
Following these steps in order reduces the probability of delays or errors in the PROSPERO registration process.
Complete the PICO and eligibility criteria before beginning the registration form. The form cannot be submitted without specific population, intervention, comparator, and outcome information. Vague or incomplete PICO fields are a common reason registrations return for revision.
Confirm that all listed co-authors have email addresses they actively monitor. Notify co-authors before submitting that they will receive a PROSPERO approval email and ask them to check spam filters if the email does not arrive within 24 hours of submission.
Select the correct risk-of-bias tool from the LATITUDES dropdown before submitting. For RCTs, select RoB 2. For non-randomized intervention studies, select ROBINS-I (V2, November 2025 revision). For diagnostic accuracy studies, select QUADAS-2. For mixed study designs, list all relevant tools.
Ensure the database list, eligibility period, and planned synthesis method fields are complete before submission. These fields are the most frequently incomplete in registrations that require manual CRD follow-up.
Do not begin searching before all co-author approvals are confirmed and the PROSPERO record has been published.
PROSPERO vs OSF vs INPLASY: Which Platform to Use
PROSPERO is not the only registration platform for systematic reviews. OSF (Open Science Framework) and INPLASY are also used, and the right choice depends on the review type and the target journal.
Table 2: Systematic Review Registration Platform Comparison (PROSPERO vs OSF vs INPLASY)
Feature | PROSPERO | OSF (Open Science Framework) | INPLASY |
|---|---|---|---|
Cost | Free | Free | Fee-based. Charges a registration fee per protocol. |
Review types accepted | Systematic reviews, rapid reviews, scoping reviews. Not narrative or literature reviews. | All research types. Not specific to systematic reviews. | Systematic reviews, meta-analyses, rapid reviews, scoping reviews. |
Journal recognition | Most widely required. Cochrane, BMJ, JAMA, The Lancet, Systematic Reviews, and most clinical journals specify PROSPERO. | Widely accepted in psychology, education, and social sciences. Less specific journal recognition in clinical medicine. | Recognized by some journals. Less universally required than PROSPERO. Check target journal requirements. |
Processing time (2025) | 24 hours (automated) to 5–10 working days (manual). Depends on submission completeness. | Immediate. No screening or approval process. | Typically, within 24–72 hours for standard submissions. |
All-author approval | Required from February 2025. The record does not publish until all co-authors approve by email. | Not required. The corresponding author registers the protocol independently. | Not required in the same structured form as PROSPERO. |
Best for | Any systematic review targeting a clinical or health journal. The default choice for health sciences. | Reviews in psychology, education, social work, and other fields where PROSPERO is not specifically required. | Reviews where a faster guaranteed turnaround is needed, and the target journal accepts INPLASY registration. Check journal requirements first. |
PROSPERO is the most widely required platform. Most Cochrane and health-related journals specify PROSPERO registration as a condition of submission. PROSPERO accepts systematic reviews, rapid reviews, and scoping reviews. It does not accept literature reviews, narrative reviews, or meta-analyses without a systematic search. The February 2025 relaunch did not change the scope of review types accepted.
OSF accepts pre-registered study protocols across all research types, including systematic reviews, but is not recognized as specifically as PROSPERO by clinical journal author guidelines. OSF is most commonly used for psychology, education, and social science reviews where PROSPERO registration is not specifically required.
INPLASY (International Platform of Registered Systematic Review and Meta-Analysis Protocols) was launched in 2020 as a fee-based alternative to PROSPERO. INPLASY charges a registration fee and offers faster processing. It is recognized by some journals, but less widely than PROSPERO. Researchers who need very fast protocol registration and whose target journal accepts INPLASY should compare the processing time against the cost.
Frequently Asked Questions
Do I need to re-register my systematic review on the new PROSPERO platform?
No. Reviews registered on PROSPERO before February 24, 2025, do not need to be re-registered. Existing records remain valid and retain their original registration dates. Some older records may show incomplete progress bars under the new mandatory field structure, but this does not affect the validity of the registration.
What happens if I accidentally list the wrong co-author or include a person who later leaves the review team?
The easiest correction before the record publishes is to cancel the submission, update the co-author list, and resubmit. After the record has been published, PROSPERO allows amendments to the registration. Amendments are logged with a date and are visible in the record history, which is consistent with the transparency purpose of the register.
Does PROSPERO 2025 require that the search has not yet begun at the time of registration?
PROSPERO strongly recommends and expects that registration precedes the database search. The platform records the planned search date and allows the actual search date to be added separately. If registration is submitted before searching begins, the review is considered prospective. If registration is submitted after the search, the review is retrospective, and this must be recorded accurately. Peer reviewers at most Tier 1 journals check whether the registration date precedes the search date.
What is the LATITUDES list and why does it matter for PROSPERO registration?
LATITUDES is a taxonomy of tools used to assess the quality or credibility of studies included in evidence syntheses. The PROSPERO team added the LATITUDES dropdown to standardize how appraisal tools are recorded across registrations. This enables more consistent searching and tracking of how different tools are used in the literature. For most clinical systematic reviews, the relevant LATITUDES tools are RoB 2 (for RCTs), ROBINS-I V2 (for non-randomized intervention studies), and QUADAS-2 (for diagnostic accuracy studies).
Can I register a scoping review on PROSPERO?
Yes. PROSPERO accepts scoping reviews. See the full scoping review methodology guide for JBI and Arksey and O'Malley approaches. The scoping review registration should specify the JBI or Arksey and O'Malley methodology being followed and whether the reporting will use PRISMA-ScR. The all-author approval requirement and similar-reviews detection apply to scoping review registrations in the same way as systematic review registrations.
How long does PROSPERO registration take under the new automated processing system?
Processing time depends on whether the submission qualifies for automated processing. Reviews with complete mandatory fields and no content requiring human editorial review may be published within 24 hours. Reviews requiring manual CRD review may take five to ten working days, consistent with the pre-2025 timeline. Build a buffer of at least two weeks into the project plan between protocol submission and planned search date to allow for all-author approval delays and any manual processing.
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Registering Your Protocol Before the Search Begins
The February 2025 PROSPERO update has made prospective registration both more rigorous and, for qualifying reviews, faster. The all-author approval requirement adds a coordination step that research teams need to plan for. The automated processing track removes the uncertainty of the previous manual screening timeline for qualifying submissions. Both changes reinforce the same principle: prospective, transparent registration before the search begins is the methodological standard, and PROSPERO's updated infrastructure supports it more explicitly.
ScribeLab Writer's protocol and PROSPERO registration service is led by credentialed researchers with published systematic reviews in the biomedical literature. The team develops PROSPERO-compliant protocols from PICO formulation through to a published record, navigating the February 2025 platform requirements, including the all-author approval process and LATITUDES field selections. Submit your project details and a PhD methodologist will respond within 2-4 hours.
