Table 3 Critical quality appraisal for included meta-analyses according to AMSTAR 2 [41]
Authors (Year) | PICO scheme used? | Review methods prior to conduct? | Explanation for inclusion of study designs? | Comprehensive literature search? |  ≥ 2 independent reviewers performed study selection? |  ≥ 2 independent reviewers performed data extraction? | List of excl. studies? | Detailed prescription of incl. studies? | RoB assessment? | Sources of funding of incl. studies mentioned? | Appropriate methods for meta-analysis? | Influence of RoB in meta-analysis? | RoB considered in interpretation/discussion of results? | Explanation for heterogeneity? | Publication bias considered? | Funding and conflict of interest stated? |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Buzelin et al. (1997) [57] | N | N | N | N | N | N | N | N | N | N | U | N | N | N | N | N |
Lowe (1994) [58] | N | N | N | N | N | N | N | N | N | N | U | N | N | N | N | Y |
Chapple et al. (1997) [59] | N | N | N | N | N | N | N | N | N | N | U | N | N | N | N | Y |