Table 2

Summary of findings and quality of evidence (GRADE)

Meta-analysisQuality assessmentParticipants, nEffectGRADE
Risk of bias*Inconsistency†Indirectness‡Imprecision§Publication bias¶IGCGIRR (95% CI)
Exercise-based prevention programmes 10 studies690064550.77 (0.61 to 0.97)Very low
Focused programmes for non-contact hamstring injuries
three studies
6775610.65 (0.44 to 0.97)Low
General programmes for non-contact hamstring injuries
three studies
141311600.63 (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.