FAQ for authors

1. What is the difference between Cochrane systematic reviews of interventions and diagnostic test accuracy review versus Cochrane systematic reviews of prognosis studies?
Systematic reviews of prognosis studies are very different from intervention and diagnostic test accuracy reviews, both methodologically and regarding the clinical question asked. Accordingly, we recommend that CRG staff attend training and workshops to learn more about prognosis research and systematic reviews of prognosis studies.
Prognosis reviews come under the complex review umbrella, and as such there is currently a requirement for dual editorial reviewing by the CRG and the PMG. Hence, all prognosis reviews should be authorised for registration and publication by the PMG and the corresponding Cochrane Review Group.

2. I would like to prepare a Cochrane prognosis review. What should I do?
As with Cochrane intervention and diagnostic test accuracy reviews you should contact the relevant Cochrane Review Group (CRG). However, please note, not all CRGs accept titles of Cochrane systematic reviews of prognosis studies. When a CRG is ready to start accepting authors' requests to register titles for prognosis reviews we recommend that the author team includes members with the following expertise:

  • A person with content expertise of the condition e.g. a clinician familiar with the target condition
  • A person with experience of preparing a systematic review of prognosis studies
  • A person with knowledge on methods of primary prognosis research
  • A person with statistical expertise or sufficient knowledge or training in the meta-analysis of prognosis studies

The CRG will assess each request to register a prognosis review. The CRG may consider:

  • – If the review falls into their scope
  • – If the review questions is suitable for a Cochrane review
  • – If the review question is a priority for their group
  • – The expertise of the review team (see above)

3. How do I find and contact the relevant CRG?
There are about 50 Cochrane review groups (CRGs) covering a wide range of medical specialties and health care. Visit the Cochrane CRG page to find the CRG that appears to be most relevant to your chosen review.

4. When can I register my title?
Each CRG will decide when it is ready to accept systematic reviews of prognosis studies from authors. Your chosen CRG may be ready to accept these reviews or may have deferred acceptance until a later date. Please contact them for details.

5. When can I start preparing my protocol?
Normally, you can prepare your protocol after your proposed title for a systematic review has been accepted by your CRG. Please contact your CRG for advice on when to start work on your protocol.
All systematic reviews of prognosis must be prepared using the most recent version of RevMan. Guidance on writing your protocol is available via tools.

FAQ for Cochrane Review Groups (CRGs)

1. Could all CRGs be prioritising and registering reviews of prognosis studies?
Yes. All CRG can consider reviews of prognosis studies. The production of reviews of prognosis studies in Cochrane is following a guided implementation process. To date there are still a limited number of published reviews of prognosis studies in the Cochrane library, as we continue to build capacity for these reviews via the Prognosis Methods Group (PMG). Currently the PMG and CRGs work in parallel both for accepting prognosis review title registrations and through the editorial process. Before registering a review title, consider that these reviews are different from therapeutic intervention and diagnostic test accuracy reviews and require specific skills and resources from both the editorial base and author teams.

2. We have an author who wants to register a systematic review of prognosis studies, what should we do?
If the CRG considers the review proposal clinically relevant, the managing editor can contact Anneke Damen, coordinator of the Cochrane Prognosis Methods Group, via CochranePMG@umcutrecht.nl. The PMG will have a look at the proposal and advice on the feasibility. The full workflow for prognosis reviews can be downloaded here.

3. We are keen to register reviews of prognosis studies in the future, but feel these are currently not a priority. What should we do?
CRGs manage large workloads and it may be important to plan when it would be appropriate to start registering systematic reviews of prognosis studies to ensure that they are in the best position to support authors. CRGs do not need to contact the PMG if they do not feel ready to support a prognosis review, and may wish to write to author teams who contact them with a request to register a review of prognosis studies explaining their decision. It may be helpful to the author to include a date when this decision may be revisited.

4. Are there specific requirements for peer review of prognosis reviews?
Yes, it is mandatory that all protocols and full reviews are peer reviewed by a member of the PMG. If the protocol or full review is ready for peer review, the CRG should contact CochranePMG@umcutrecht.nl to obtain the contact details of an independent PMG reviewer assigned to that protocol/review. Peer review templates for prognosis reviews can be downloaded on our tools page.

5. Should we be developing a specialist register of studies?
There is no expectation that Cochrane Review Groups maintain a specialized register of prognosis studies for their group. However, if they have the capacity to do so, it will be welcomed, and potentially useful in the long run.

6. How do we develop our topic list and look for "areas of common interest"?
At present we think that CRGs will not have to develop a separate topic list. It may be more useful for CRGs to scope out good clinical questions regarding prognosis if they come across these questions. This may help prioritization of prognosis questions. However, it is not necessary or mandatory to maintain such a list.

7. What resources should we send or recommend to authors?
The PMG is maintaining an up to date overview of the most important methods papers for systematic reviews of prognosis studies. This overview is available via our website. Also, the most recent versions of the title proposal form, protocol and review template, and peer review templates are available via this link.

FAQ for authors and CRGs

1. Are there different types of prognosis reviews?
Yes, there are different types. Cochrane reviews can focus on studies of overall prognosis, prognostic factors or prognostic models.
Studies on overall prognosis give insight in the occurrence of certain outcomes in a certain time frame, for a group of individuals with a certain health condition (not necessarily a disease).
Studies on prognostic factors identify variables that are prognostic for a certain outcome in a certain individual within a given timeframe.
Prognostic model studies combine prognostic factors in a single model to make personalized predictions for individuals with a certain health condition. Prognostic model studies can focus on the derivation of such a model, or the transportability or generalizability of a model to other populations.
A fourth type of prognosis studies investigates predictors of treatment effect. These studies aim to identify individuals’ factors that are associated with the effectiveness of a certain treatment. Reviews of this fourth type of prognosis studies are not yet supported by Cochrane.

2. Are there webinars on reviews of prognosis?
A webinar (recorded in September 2018) is available via the Cochrane Training website. It provides an introduction to the steps of a review of prognosis studies and highlights the templates available for protocols and full reviews.

3. Is there a template for protocols and full reviews?
Templates for protocols and full reviews are available via tools. Authors are asked to manually add the proposed headings in RevMan and follow the instructions in the templates.

4. Does RevMan Web support reviews of prognosis studies?
Not yet. Reviews of prognosis studies cannot be written in RevMan Web yet. Reviews of prognosis studies should currently be registered as a Flexible review. We are in the process of creating a template for prognosis reviews in RevMan Web.

5. Is there specific guidance for risk of bias?
Tools for risk of bias assessment are available for prognostic factor studies and prognostic model studies. For prognostic factor studies, reviewers should use the QUIPS tool, and for prognostic model studies the PROBAST tool should be used. No tool is available for overall prognosis studies. We advise the modify either the QUIPS tool by removing the domains about prognostic factors and adjustment for other prognostic factors, or the PROBAST tool by removing some signaling questions from the domain predictors and outcome and the entire domain analysis.

6. Is there specific guidance for GRADE?
GRADE guidance is available for reviews of prognostic factor studies and there is also guidance for reviews of overall prognosis studies. Work is underway to produce guidance for grading the quality of evidence for reviews of prognostic model studies, but it will be a while before this is available to author teams. Hence, we neither expect author teams of prognostic model reviews to provide assessments for GRADE quality of evidence, nor adapt the GRADE framework for these types of reviews.

7. Are summary of findings tables required / are they different to intervention reviews?
As no guidance exists for summary of findings tables of reviews of prognosis studies, it is not required to produce such a table. Reviewers who nevertheless want to present a summary of findings table are referred to the existing reviews that have already been published. See ongoing reviews.

8. Are there existing reviews we take as an example?
An overview of all published Cochrane reviews and protocols is available under ongoing reviews.

9. Is there a handbook for Cochrane reviews of prognosis studies?
No at the moment there is no handbook for Cochrane reviews of prognosis studies. The PMG is considering developing a handbook for prognosis reviews. However there is plenty of relevant literature out there. Some relevant useful publications can be found in the PMG website, under tools.

10. Who should we approach for methods support? Can the PMG provide methods support?
The PMG provides support in the form of peer review of the review proposal form, protocol, and full review. This PMG peer review is mandatory for all reviews of prognosis studies. Further, active methods support by the PMG is unfortunately not possible due to lack of resources. All support the PMG can provide is non-funded. Authors are therefore themselves responsible for composing an author team consisting of sufficient methodological and statistical knowledge.