Table 3.

Class profiles of substance use and medication adherence

	Proportion of total sample reporting use n = 557	Frequency of use among active substance users n = 469	Frequency of Use among Use Pattern n (= 469)				Test Statistic
	Proportion of total sample reporting use n = 557	Frequency of use among active substance users n = 469	Class 1 Exclusive Alcohol Use n = 106	Class 2 Alcohol and Marijuana n = 85	Class 3 Alcohol and Cocaine/Crack n = 146	Class 4 Multiple-Substance Use n = 132	Test Statistic

Days of use	n (%)	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)

Alcohol	414 (74.3)	10.4 (10.4)	7.5 (9.5) ^a	11.4 (11.2) ^b	8.6 (9.7) ^a	14.2 (10.3) ^b	χ²(3) = 33.3^**
Marijuana	233 (41.8)	7.2 (10.6)	0.02 (0.1) ^a	15.6 (10.5) ^b	0.1 (0.24) ^c	15.6 (12.3) ^b	χ²(3) = 462.1^**
Cocaine/Crack	252 (45.2)	5.7 (8.4)	^†	^†	7.7 (7.9) ^a	11.7 (11.6) ^b	χ²(1) = 13.5^**
Opiates	86 (15.4)	2.3 (6.8)	^†	^†	3.4 (10.5)	4.7 (14.5)	χ² (1) = 0.7
Poppers	53 (9.5)	1.0 (4.2)	0.6 (2.8)	0.6 (2.7)	0.9 (4.7)	1.8 (4.1)	χ²(3) = 5.8
Other Drug ^††	65 (11.7)	1.8 (6.7)	0.1 (0.5) ^a	1.1 (4.1) ^b	1.8 (8.3) ^b	3.6 (16.2) ^b	χ²(3) = 32.2^**

	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)

AUDIT score (range 0–12)	4.3 (3.5)	5.1 (3.3)	4.3 (3.1) ^a	4.4 (3.1) ^a	4.8 (3.5) ^a	6.5 (2.7) ^b	F (3, 465) = 12.6^**
DAST score (range 1–10)	3.9 (3.4)	4.6 (3.3)	0.5 (1.5) ^a	4.1 (2.5) ^b	6.0 (2.5) ^c	6.6 (2.3) ^c	F (3, 465) = 174.6^*

	n (%)	n (%)	n (%)	n (%)	n (%)	n (%)

Injection Drug Use	33 (5.9%)	33 (7.0)	0 (0.0) ^a	1 (1.2) ^a	16 (11.0) ^b	16 (12.1) ^b	?²(3) = 21.1^**

p =.05

^**

p =.01

^†

Empty cell not included in follow up ANOVA

^††

Amphetamines, sedatives, PCP, and solvents

Note: Where omnibus tests of between group differences were significant, group-by-group comparisons were evaluated using the LSD (count variables), Games-Howell (continuous variables with unequal cell variances), or Ficher Exact (for categorical variables) po Groups with different superscripts differ at p < .05. Groups which share a common superscript do not.