Methodological quality | Source of funding | Yes (Low risk) | No (High risk) | Unclear | Chi-square p value | Fisher’s exact p value |
---|---|---|---|---|---|---|
N = 67 studies | n (%)$$ | n (%)$$ | n (%)$$ | |||
Sequence generation | Industry | 26 (38.8) | Â | 14 (20.9) | 0.435 | 0.465 |
 | None/Not clear | 8 (11.9) |  | 8 (11.9) |  |  |
 | Non industry | 8 (11.9) |  | 3 (4.5) |  |  |
Allocation concealment | Industry | 21 (31.3) | Â | 19 (28.4) | 0.315 | 0.338 |
 | None/Not clear | 5 (7.5) |  | 11 (16.4) |  |  |
 | Non Iindustry | 6 (9.0) |  | 5 (7.5) |  |  |
Blinding | Industry | 18 (26.9) | Â | 22 (32.8) | 0.395 | 0.457 |
 | None/Not clear | 6 (9.0) |  | 10 (14.9) |  |  |
 | Non industry | 7 (10.4) |  | 4 (6.0) |  |  |
Incomplete outcome data | Industry | 36 (53.7) | 1 (1.5) | 3 (4.5) | 0.023* | 0.005* |
 | None/Not clear | 9 (13.4) |  | 7 (10.4) |  |  |
 | Non industry | 7 (10.4) |  | 4 (6.0) |  |  |
Selective reporting | Industry | 36 (53.7) | 2 (3.0) | 2 (3.0) | 0.224 | 0.188 |
 | None/Not clear | 11 (16.4) | 4 (6.0) | 1 (1.5) |  |  |
 | Non industry | 10 (14.9) | 1 (1.5) | 0 |  |  |
Free of other bias | Industry | 35 (52.2) | Â | 5 (7.5) | 0.033* | 0.038* |
 | None/Not clear | 9 (13.4) |  | 7 (10.4) |  |  |
 | Non industry | 8 (13.4) | 1 (1.5) | 2 (3.0) |  |  |