TABLE 1.
Rating of included studies according to AMSTAR quality criteria1
| Criterion # | AMSTAR quality criteria | Yes n (%) | No n (%) |
|---|---|---|---|
| 1 | A priori design | 105 (89) | 13 (11) |
| 2 | Duplicate study selection and data extraction | 86 (73) | 32 (27) |
| 3 | Comprehensive literature search | 108 (92) | 10 (8) |
| 4 | Status of publication used as inclusion criteria (gray literature included) | 89 (75) | 29 (25) |
| 5 | List of studies provided, both included and excluded | 68 (58) | 50 (42) |
| 6 | Characteristics of included studies | 107 (91) | 11 (9) |
| 7 | Scientific quality of included studies assessed and documented | 88 (75) | 30 (25) |
| 8 | Scientific quality of included studies used appropriately for formulating conclusions | 69 (58) | 49 (42) |
| 9 | Methods used to combine findings appropriate | 109 (92) | 9 (8) |
| 10 | Likelihood of publication bias assessed | 63 (53) | 55 (47) |
| 11 | Conflict of interest stated | 49 (42) | 69 (58) |
1AMSTAR, Assessing the Methodological Quality of Systematic Reviews.