Abstract

We are writing to correct our editorial on AMSTAR 2.0 quality of Campbell systematic reviews. Upon receiving feedback from Campbell authors on the rating of their reviews, we found that our operationalization of the AMSTAR 2.0 tool was overly strict for two items: (1) listing the excluded studies and providing justification for their exclusion (item 7), and (2) investigation of publication bias and discussing its likely impact on the review findings (item 15). Both of those items are critical items which significantly affects the overall quality rating. We consulted with the lead author of AMSTAR2 (Bev Shea) and the detailed AMSTAR2 guidance and we reevaluated all the reviews which were rated as not meeting these two criteria.
For item 7: listing the excluded studies and providing justification for their exclusion, we initially required a table with all of the excluded studies and reasons for exclusion to rate this as “yes.” On re-evaluation, we identified reviews which reported a list of “near misses” (Higgins et al., 2023; The Methods Group of the Campbell Collaboration, 2017) or examples of excluded studies with rationales for exclusion in the text. We adjusted those reviews to “yes” if all studies were listed and “partial yes” if excluded studies were partially listed.
For item 15: investigation of publication bias and discussing its likely impact on the review findings, we required that reviews described how they assessed publication bias
The following updates were made in page one (paragraph 4): Regarding the overall methodological quality of the Campbell reviews from 2018 to 2022, Sources of funding for the included studies ( Assessed potential impact of risk of bias in individual studies on the results of the meta-analysis or other evidence synthesis ( The following updates were made in page one (paragraph 5): Compared to the reviews published before 2018, the overall methodological quality of the recent reviews has generally improved (Figure 1). The proportion of high-quality reviews has doubled (17% to In the page one (paragraph 6), we updated the sentence “However, reporting the source of funding and the impact of risk of bias in individual studies on the results of the meta-analysis were persistently inadequately considered but more frequently observed in the last 5 years (15% to In page one, paragraph 7, we deleted the “ We have updated Figure 1, Figure 2, and

Overall methodological quality of Campbell systematic reviews.

Changes in reporting of AMSTAR 2.0 items reported in less than 70% of Campbell reviews in 2011–2018.
References
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