Systematic reviews supporting practice guideline recommendations lack protection against bias

Ref ID	333
First Author	J. P. Brito
Journal	JOURNAL OF CLINICAL EPIDEMIOLOGY
Year Of Publishing	2013
URL	https://www.jclinepi.com/article/S0895-4356(13)00031-0/pdf
Keywords	• Low reporting quality • Grey literature • Protocols • Single reviewer • Low methodological quality • Endocrinology
Problem(s)	• No registered or published protocol • Grey literature excluded • Reasons for excluding potentially eligible studies not provided • Single reviewer / lack of double checking • Poor consideration of publication bias • Low methodological (AMSTAR) quality
Number of systematic reviews included	69
Summary of Findings	Included reviews had a mean AMSTAR score of 6.4 (standard deviation, 2.5) from a maximum score of 11, with scores improving over time. Systematic reviews of randomized trials had higher AMSTAR scores than those of observational studies. Low-quality systematic reviews (methodological AMSTAR score 1 or 2 of 5, n 5 24, 35%) were cited in 24 different practice recommendations and were the main evidentiary support for five recommendations, of which only one acknowledged the quality of systematic reviews
Did the article find that the problem(s) led to qualitative changes in interpretation of the results?	N/A
Are the methods of the article described in enough detail to replicate the study?	No