Conduct standards specific to updates
|Standard||Rationale and elaboration||Resources|
|Undertake a new search||
An updated review must include an update search for new (or additional) studies. For issues to consider in planning the search, see MECIR update standard U4.
The most recent search must be no more than 12 months (preferably six months) from the intended publication date, and the results screened for potentially eligible studies.
See MECIR conduct standard C37: Rerun or update searches for all relevant databases within 12 months before publication of the review or review update, and screen the results for potentially eligible studies.
|See Handbook Section IV.4 and Section 4.4.10|
|U7||Including new studies||Mandatory|
|Implement conduct standards for study selection and data collection for any newly identified studies (with updated criteria or methods as determined above).||MECIR conduct standards C39 - C51||
See Handbook Section 4.4.6, Section 5.3.6, Section 4.6.3, Section 4.6.4, Section 4.6.2, Section 5.2, Section 5.2.1, Section 5.2.3, Section 5.3.1, Section 5.3.6, Section 5.4.1 and Section 5.5.2
|U8||Reconsider previously identified studies||Mandatory|
|Consider studies previously identified as included, awaiting classification, ongoing and excluded, and collect additional information from them if necessary.||
Ensure appropriate methodology is followed to select included studies and collect information from them.
It will be necessary to establish whether any studies previously identified as ongoing have now been completed.
Ensure that reasons for excluding studies are consistent with current eligibility criteria and methodological standards.
A redesign of the data collection form may be required if review questions or objectives have been modified.
|U9||Assessing risk of bias||Mandatory|
|Ensure all studies are consistently assessed for risk of bias.||
The updated review must include a ‘Risk of bias’ assessment of all new and previously included studies. If the previous version used the original risk of bias tool to assess randomised trials, consider whether or not to switch to the Risk of Bias 2 tool (see Handbook (version 6) Chapter 8), including how many randomised trials were assessed in the previous version, how many new studies are expected for inclusion in the update, how well it was implemented in the previous version and whether it is feasible to switch.
|See Handbook Section 7.1.2, Section 7.3.2, Section 7.5, Section 7.6.1, Section 7.8.6 and Chapter 8.|
|Implement review synthesis methods (possibly revised for the update) according to conduct standards for synthesis, across all included studies.||MECIR conduct standards C61 - C73||See Handbook Section 6.2.1, Section 6.2.9, Section 10.5.3, Section 10.10.2, Section 10.10.3, Section 10.11.3.1, Section 10.11.5.2, Section 10.12.1, Section 10.14, Chapter 11, Section 13.4, Section 15.3.1|
|U11||Assessing the certainty of evidence||Mandatory|
|Assess certainty of evidence using GRADE considerations of risk of bias, inconsistency, imprecision, indirectness and publication bias.||
This must be applied to the full body of evidence for the key outcomes included in the updated review. The most convenient way to present GRADE assessments is in a ‘Summary of findings’ table.
MECIR conduct standards C74-C75 and MECIR reporting standard R97
|See Handbook Section 14.2.1|