Table 3.

Pooled estimate, 95% confidence interval, and heterogeneity statistics for the dependent variables of the study.

Injuries	k	N	${\mathit{\text{IRR}}}^{+}$	95%CI	95%PI	${\tau }^2$	$I^2$	$Q$	p
Total	21	18305	0.624	[0.538, 0.725]	[0.352, 1.108]	0.070	75.58	80.08	<0.001
Lower limbs	17	13898	0.634	[0.541, 0.743]	[0.382, 1.054]	0.052	62.30	44.18	<0.001
Thighs	13	11425	0.712	[0.524, 0.968]	[0.440, 1.151]	0.029	11.45	13.89	0.308
Knees	13	11425	0.659	[0.499, 0.871]	[0.342, 1.271]	0.074	40.73	18.71	0.096
Ankles	13	11425	0.610	[0.431, 0.862]	[0.228, 1.633]	0.179	62.87	29.51	0.003

k = number of independent samples included in the analysis; N = total sample size; ${\mathit{\text{IRR}}}^{+}$ = pooled effect size estimate (Incidence rate ratio); 95%CI = lower and upper bounds of the 95% confidence interval; 95%PI = lower and upper bounds of the 95% prediction interval; ${\tau }^2$ =Paule-Mandel estimate for the between-study variance; $I^2$ = heterogeneity index; Q = Cochran's heterogeneity statistic with $k-1$ degrees of freedom; p = p-value for the Cochran's heterogeneity statistic.