Changes in Specific Substance Involvement Scores among SBIRT recipients in an HIV primary care setting

Table 3 Estimated change in Specific Substance Involvement Scores over 6 months for PLHIV SBIRT intervention participants at lower compared to moderate–high risk at baseline

Substance	Effect^a	Coefficient^b	95% BC CI^{b, c} Lower, upper limit
Tobacco	Months—lower	0.38	0.15, 0.65
	Months—M–H	− 0.16	− 0.44, 0.13
	Risk category	18.31	16.71, 19.90
	Month by risk	− 0.54	− 0.93, − 0.17
	Intercept^d	1.57
Alcohol	Months—lower	0.30	0.09, 0.51
	Months—M–H	− 1.29	− 1.84, − 0.75
	Risk category	17.44	15.44, 19.37
	Month by risk	− 1.59	− 2.19, − 1.00
	Intercept	4.06
Cannabis	Months—lower	0.52	0.17, 1.02
	Months—M–H	− 0.40	− 0.84, 0.03
	Risk category	13.68	11.81, 15.69
	Month by risk	− 0.92	− 1.60, − 0.36
	Intercept	1.36
Cocaine	Months—lower	0.30	0.06, 0.63
	Months—M–H	− 0.52	− 1.01, − 0.01
	Risk category	16.48	14.06, 19.03
	Month by risk	− 0.82	− 1.39, − 0.25
	Intercept	1.28
Amphetamine	Months—lower	0.09	− 0.03, 0.21
	Months—M–H	− 0.61	− 1.22, − 0.02
	Risk category	15.95	13.56, 18.43
	Month by risk	− 0.69	− 1.32, − 0.10
	Intercept	0.75
Inhalants	Months—lower	0.17	0.06, 0.32
	Months—M–H	− 0.72	− 1.40, − 0.09
	Risk category	7.23	4.65, 10.16
	Month by risk	− 0.89	− 1.58, − 0.24
	Intercept	0.33
Sedatives	Months—lower	0.09	− 0.01, 0.21
	Months—M–H	− 1.50	− 2.12, − 0.83
	Risk category	12.19	9.77, 14.96
	Month by risk	− 1.58	− 2.21, − 0.92
	Intercept	0.62
Hallucinogens	Months—lower	0.16	0.05, 0.30
	Months—M–H	− 1.68	− 3.05, − 0.02
	Risk category	11.49	7.61, 15.86
	Month by risk	− 1.84	− 3.22, − 0.18
	Intercept	0.31
Opioids	Months—lower	0.19	0.05, 0.35
	Months—M–H	− 1.13	− 1.93, − 0.17
	Risk category	13.68	10.87, 16.53
	Month by risk	− 1.31	− 2.13, − 0.36
	Intercept	0.72

^aEffects in each multilevel regression model. Months—lower is simple slope over time for lower risk category; months—M–H is simple slope over time for moderate–high risk category; reference group for risk category at baseline = 0 (lower risk); month by risk is the cross-level interaction (equivalent to the difference between the two simple slopes, with lower risk as the reference category; the display with only two decimals sometimes results in rounding errors in the table)
^bThe nonparametric, bootstrapped 95% bias-corrected confidence interval from 5000 repetitions
^cThe coefficient is significant if zero is not in the interval
^dThe test of the intercept against zero is not a hypothesis test of interest

ISSN: 1940-0640