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 • Pre-specification
• General medical
• Protocols
Problem(s) • Undocumented or unjustified deviations to the review protocol
Article Type Empirical
Article Subtype Cross-sectional survey/Methodological systematic review
First Author Country Germany
Checklists • PRISMA-P
Aim To assess the prevalence of differences in the reported methods between non-Cochrane systematic reviews published up to 2016 and their published protocols and the extent to which these were reported and explained.
Level of Investigation Descriptive
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)
Number of systematic reviews included 80
Number of eligible systematic reviews assessed 214
Treatment impacted No
Treatment impacted description
Interpretation impacted Not Applicable
Interpretation impacted description