The GRADE approach for Cochrane systematic reviews on public health: a meta-epidemiological study

Article type
Authors
Li X1, Liang S1, Yang C1
1Centre for Evidence-Based Social Science/Center for Health Technology Assessment, School of Public Health, Lanzhou University, Lanzhou, China; Centre for Evidence-Based Medicine, School of Basic Medical Science, Lanzhou University, Lanzhou, China
Abstract
"Objective: This study aimed to analyze the characteristics of the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) used in Cochrane systematic reviews (CSRs) on public health.
Methods: The Cochrane Library was searched in October 2021 to identify CSRs on public health. The CSRs were rated using the GRADE approach and assessed by the AMSTAR-2 tool. Finally, descriptive analyses of included CSRs were performed for the epidemiological characteristics of GRADE.
Result: 54 CSRs published between 2011 and 2021 were included in this study, most of which focused on nutrition (31%), health systems (15%), occupational health (14%), and environmental health (12%). Besides, most of the CSRs were randomized controlled trials (83%). The methodological quality of the CSRs was either high (89%) or moderate (11%). A total of 619 outcomes were respectively rated as being of high (4%), moderate (16%), low (38%), and very low (42%) evidence quality by GRADE. Among the five downgrade factors of GRADE, the most prevalent were risk of bias (68%), imprecision (34%), and indirectness (16%). However, only the magnitude of effect size was prevalent among the upgrade factors.
Conclusion: On public health, the usage of GRADE approach need to be strengthened in systematic reviews, and the risk of bias, imprecision, and indirectness are the main factors impacting the evidence quality."