Comparison of non-Cochrane systematic reviews and their published protocols: differences occurred frequently but were seldom explained

Ref ID 342
First Author N. Koensgen
Journal JOURNAL OF CLINICAL EPIDEMIOLOGY
Year Of Publishing 2019
URL https://www.jclinepi.com/article/S0895-4356(18)30903-X/fulltext
Keywords Protocols
Pre-specification
General medical
Problem(s) Undocumented or unjustified deviations to the review protocol
Number of systematic reviews included 80
Summary of Findings Almost all included systematic reviews (92.5%) differed from their protocols in at least one of the methods-related PRISMA-P items and their subcategories. Half the systematic reviews (48.8%) had a major difference in at least one item. On average, each systematic reviews differed from its protocol in 3.2 items PRISMA-P, of which one comprised a major difference. Only 10% of all differences were reported in the systematic review, two-thirds with an explanation (7.0% in total)
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? Yes