. Author manuscript; available in PMC: 2014 Sep 10.

Published in final edited form as: Psychol Addict Behav. 2008 Mar;22(1):78–87. doi: 10.1037/0893-164X.22.1.78

Table 4.

Subject–Collateral Agreement by Urine Drug Screen Result (Continuous Variables)

	Positive drug screen		Negative drug screen
Substance use variable	ICC	n	ICC	n
Total no. of drinks	.22^*	56	.29^**	94
No. of drinking days	.16	62	.39^***	97
No. of heavy drinking days	.23^*	59	.45^***	97
Ave. drinks per drinking day^a	.00	30	.57^***	25
Ave. drinks per day	.15	58	.25^**	95
No. of days used illicit drugs	.03	58	.32^***	96
No. of days used marijuana	.16	50	.38^***	96
No. of days used cocaine/crack	.39^***	56	.38^***	94

Note. Drug test results are based on subjects' drug urine screens at baseline. All variables are from collateral and subject Timeline Follow-Back data. ICC = intraclass correlation for subject–collateral reports; Ave. = average.

Variable for which the correlations are significantly different at p < .05.

p < .05.

^**

p < .01.

^***

p < .001.