Reporting, handling and assessing the risk of bias associated with missing participant data in systematic reviews: a methodological survey

Ref ID 144
First Author E. A. Akl
Journal BMJ OPEN
Year Of Publishing 2015
Keywords Cochrane
Missing data
Risk of bias
General medical
Non-Cochrane reviews
Problem(s) Failure to address missing outcome data in analyses
Cochrane reviews more rigorous/higher quality than non-Cochrane reviews
Ignores setting or context of included studies which limits review applicability
Flawed risk of bias undertaken
Number of systematic reviews included 202
Summary of Findings Of 98 Cochrane and 102 included non-Cochrane reviews, 47% and 7% (p<0.0001), respectively, reported on the number of participants with missing data, and 41% and 9% reported a plan for handling missing categorical data. 65% of reviews assessed risk of bias associated with missing data; this was associated with Cochrane reviews (relative to non- Cochrane: OR=6.63; 95% CI 2.50 to 17.57, p=0.0001), and the use of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology (OR=5.02; 95% CI 1.02 to 24.75, p=0.047).
Did the article find that the problem(s) led to qualitative changes in interpretation of the results? Not Applicable
Are the methods of the article described in enough detail to replicate the study? No