MECIR Manual
Description of studies (R56-72)

Description of studies

  Standard Rationale and elaboration Resources
R56 Flow of studies Mandatory  
  Provide information on the flow of studies from the number(s) of references identified in the search to the number of studies included in the review, ideally using PRISMA type flow diagram. Clarify how multiple references for the same study relate to the individual studies. 

MECIR conduct standard 41: Document the selection process in sufficient detail to complete a PRISMA flow chart and a table of ‘Characteristics of excluded studies’.

MECIR conduct standard 42: Collate multiple reports of the same study, so that each study, rather than each report, is the unit of interest in the review.

Cochrane Training resource: searching for studies

CIL: module 4 - selecting studies and collecting data

R57 Lack of included studies Highly desirable  
  If a review identifies no eligible studies, restrict the Results section to a description of the flow of studies and any brief comments about reasons for exclusion of studies. Under ‘ Risk of bias in included studies’ and ‘Effects of interventions’, state “No study met the eligibility criteria”. Any discussion of evidence not meeting the eligibility criteria of the review should be in the Discussion section.  
R58 Excluded studies Mandatory  
  List key excluded studies and provide justification for each exclusion.  The table of ‘Characteristics of excluded studies’ is intended as an aid to users rather than a comprehensive list of studies that were identified but not included. List here any studies that a user might reasonably expect to find in the review to explain why they are excluded.

See Handbook 7.2.5

Cochrane Training resource: selecting studies

CIL: module 4 - selecting studies and collecting data

 

R59 Studies awaiting classification Highly desirable  
  List the characteristics of any completed studies that have been identified as potentially eligible but have not been incorporated into the review.  Users of the review will be interested to learn of any potentially relevant studies that have been conducted and are known to the review team, but have not yet been incorporated in to the review irrespective of their publication status. This will help them to assess the stability of the review findings. These should be listed in the table of ‘Characteristics of studies awaiting classification’, along with any details that are known. Authors should also consider the impact of not including these studies on the review findings as a potential limitation, and the extent to which they affect the implications for research.

Cochrane Training resource: searching for studies

CIL: module 3 - searching for studies

R60 Ongoing studies Mandatory  
  Provide details of any identified studies that have not been completed. 

Users of the review will be interested to learn of any potentially relevant studies that have not been completed. This will help them to assess the stability of the review findings. These should be listed in the table of ‘Characteristics of ongoing studies’, along with any details that are known.

Cochrane Reviews should be mindful of research waste so it is useful to consider how ongoing studies might address the review question under ‘Implications for research’. 

Cochrane Training resource: searching for studies

CIL: module 3 - searching for studies

 

R61 Table of ‘Characteristics of included studies’ Mandatory  
  Present a table of ‘Characteristics of included studies’ using a uniform format across all studies.  MECIR conduct standard 44: Collect characteristics of the included studies in sufficient detail to populate a table of ‘Characteristics of included studies’.

Cochrane Training resource: collecting data

CIL: module 8 - reporting the review

R62 Included studies Mandatory  
  Provide a brief narrative summary of any included studies. This should include the number of participants and a summary of the characteristics of the study populations and settings, interventions, comparators and funding sources.     

See Handbook 4.5

CIL: module 8 - reporting the review

R63 Table of ‘Characteristics of included studies’: methods  Mandatory  
  Provide the basic study design or design features (e.g. parallel group randomized trial, cluster-randomized trial, controlled before and after study). Even if the review is restricted to one study design, these tables should provide a comprehensive summary of each study. It is important that labels used to describe study designs are clearly defined in the review. 

See Handbook 13.2

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

 

R64 Table of ‘Characteristics of included studies’: participants Mandatory  
  Provide sufficient information about the study populations to enable a user of the review to assess the applicability of the review’s findings to their own setting.   Information presented in this table should reflect the baseline demographics of the study sample. In addition, it is helpful to state the eligibility criteria of the study.

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R65 Table of ‘Characteristics of included studies’: sample sizes Mandatory  
  Include the sample size for each included study in the table of ‘Characteristics of included studies’.  If sample sizes are available for each intervention group, these should be included. A convenient place is often within the box for Interventions, e.g. inserting “(n =  )” after each listed intervention group. 

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R66 Table of ‘Characteristics of included studies’: interventions Mandatory  
  Provide sufficient information to enable users of the review to assess the applicability of the intervention to their own setting, and if possible in a way that allows the intervention to be replicated. The components of all interventions (drug, non-drug, simple or complex) should be reported. Reporting guidelines have been developed for describing interventions used in primary research and review authors may find it useful to structure their description of interventions around the core attributes highlighted by TIDieR (Hoffman 2014). Lengthy explanations of interventions should be avoided. Citations to sources of detailed descriptions can be included. 

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R67 Table of ‘Characteristics of included studies’: outcomes Mandatory  
  Provide clear and consistent information about outcomes measured (or reported), how they were measured and the times at which they were measured. It should be clear whether main outcomes of interest in the review were measured in the study.

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R68 Table of ‘Characteristics of included studies’: dates Highly desirable  
  Include the dates when the study was conducted in the table of ‘Characteristics of included studies’. If dates are not available then this should be stated (e.g. “Study dates not reported”).

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R69 Table of ‘Characteristics of included studies’: funding source Mandatory  
  Include details of funding sources for the study, where available.  Details of funding sources should be placed in this table rather than as part of the ‘Risk of bias’ table. Including an extra row in the table of ‘Characteristics of included studies’ is encouraged.

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R70 Table of ‘Characteristics of included studies’: declarations of interest Mandatory  
  Include details of any declarations of interest among the primary researchers.   Declarations of interest should be placed in this table rather than as part of the ‘Risk of bias’ table. Including an extra row in the table of ‘Characteristics of included studies’ is encouraged.

Cochrane Training resource: collecting data

CIL: module 4 - selecting studies and collecting data

R71 Choice of intervention groups in multi-arm studies Highly desirable  
  If a study is included with more than two intervention arms, restrict comments on any irrelevant arms to a brief comment in the table of ‘Characteristics of included studies’.

Intervention arms that are not relevant to the review question should not be discussed in detail, although it is useful to clarify (in this table) that such arms were present.

MECIR conduct standard 50: If a study is included with more than two intervention arms, include in the review only intervention and control groups that meet the eligibility criteria.)

Cochrane Training resource: analysing non-standard data and study designs

CIL: module 6 - analysing the data 

R72 References to included studies Mandatory  
  List all reports of each included study under the relevant Study ID. It is important that all reports are listed, and are grouped by study. Marking one report as the primary reference is helpful where appropriate.  

 

Section info
Contact
ldunn@cochrane.org
Describe change
R56: Provide information on the flow of studies from the number(s) of references identified in the search to the number of studies included in the review, ideally using a flow chart. Clarify how multiple references for the same study relate to the individual studies. Changed to: Provide information on the flow of studies from the number(s) of references identified in the search to the number of studies included in the review, ideally using a PRISMA type flow diagram. Clarify how multiple references for the same study relate to the individual studies.
Change date
12 October 2018