Table 1.

Reliability of ICIAIs and psychosocial measurement scales

Scales	Items	Cronbach's alpha
		Boys	Girls
Family ICIAI	18	0.90	0.88
Friend ICIAI	18	0.87	0.87
Classmate ICIAI	18	0.85	0.88
Favorable attitude towards heroin use	7	0.84	0.78
Perceived behavioral control	10	0.86	0.81
Perceived peer control	6	0.77	0.71
Communication with parent about heroin use	10	0.80	0.83