TABLE 5.

Moderators analysis.

Moderator	k	R 2 (%)	QM	df	P‐value
Population	13	60.49	19.87	2	<.0001
Type of prevalence reported	13	17.03	3.41	1	.06
Case ascertainment	13	0	1.05	1	.31
Origin	13	0	0.23	1	.63
Quality of study	13	0	0.12	1	.73
Year of publication	13	0	0.28	1	.60
Mean age	10	0.31	0.94	1	.33
Percentage of women	11	0	0.08	1	.78

Abbreviations: df, degree of freedom; k, number of studies; QM, omnibus test; R ² (%), coefficient of determination en %.