Table 1.

Characteristics of the studies included in the meta-analyses

	Gonadal axis		Cotricotropic axis
Number of studies	Total (n = 15)	Missing	Total (n = 5)	Missing
Total number of participants	3250	0	207	0
Median number of participants per study (range)	38 (12–1585)	0	48 (20–81)	0
Median % male (range)	100 (36–100)	1	52 (40–65)	1
Median mean age (range), years	50 (38–60)	2	50 (43–54)	1
Median duration of opioid use (range), months	26.6 (6–100)	8	18 (0–27)	2
Median long-term follow-up, months	9 (0–27)	11	9 (0–27)	1