Meta-analysis | Quality assessment | Participants, n | Effect | GRADE Quality | |||||
Risk of bias* | Inconsistency† | Indirectness‡ | Imprecision§ | Publication bias¶ | IG | CG | IRR (95% CI) | ||
Exercise-based prevention programmes 10 studies | ◯ | ⨁ | ◯ | ⨁ | ◯ | 6900 | 6455 | 0.77 (0.61 to 0.97) | Very low ⨁⨁◯◯◯ |
Focused programmes for non-contact hamstring injuries three studies | ◯ | ⨁ | ⨁ | ◯ | – | 677 | 561 | 0.65 (0.44 to 0.97) | Low ⨁⨁◯◯ |
General programmes for non-contact hamstring injuries three studies | ◯ | ◯ | ◯ | ◯ | – | 1413 | 1160 | 0.63 (0.19 to 2.12) | Very low ◯◯◯◯ |
*More than 25% of participants from studies with ‘high risk of bias’.
†Downgraded by one level considering: the proportion of the observed variance may be substantial (I2 >50%), visual inspection for minimal or no overlap of CIs, and χ2 test.
‡Based on the characteristics of participants included in the meta-analysis.
§Downgraded if the upper and lower CIs had >0.5 difference; or if the clinical course of action differed considering the upper and lower CI as the true estimate.
¶Assessed with visual inspection of the funnel plot and two-tailed Egger test (if >10 studies were included in the meta-analysis).
CG, control group; IG, intervention group; IRR, injury risk ratio.