Table 4.

The percentage of poor sleepers [Pittsburgh Sleep Quality Index (PSQI) > 5] comparisons among healthy controls, mainly heroin users (heroin or other drug users) and MA users in samples of overall, male, and female, respectively.

	Controls	MA users	Mainly heroin users	P*
Overall	26.4%	54.2%	79.8%	<0.001
Male	26.0%	52.4%	80.8%	<0.001
Female	28.8%	75.6%#	75.1%#	<0.001

*Significantly different from male group, p<0.01.

^#No significant differences between female heroin and female MA groups, p = 0.926.