case_images: PMC8071979_01
case_images: Selection of studies for the meta-analysis (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).
case_images: 10.1177_17534666211009407-fig1.jpg
case_images: PMC8071979_01_10.1177_17534666211009407-fig1.jpg
case_images: fig1-17534666211009407
case_images: The Newcastle-Ottawa quality assessment scale (NOS) checklist (Supplementary material Figure S1 online) was used to assess the quality of eligible studies.