Table 4.

Effect of race on self-reported number of substances used, controlling for age.

Independent Variable	Dependent Variable	βCoefficient	Confidence Interval	P-value
Number of Substance Classes
Lifetime Use	Age	−0.016	−0.035–0.0039	0.117
	Race: White	0.96	0.52–1.40	<0.001***
Before Non-Pharmaceutical Opioids	Age	−0.024	−0.048-−0.00042	0.046
	Race: White	1.23	0.69–1.77	<0.001***
Number of Substances
Lifetime Use	Age	−0.084	−0.14-−0.032	0.002
	Race: White	2.33	1.18–3.48	<0.001***
Before Non-Pharmaceutical Opioids	Age	−0.049	−0.088-−0.0092	0.016
	Race: White	1.45	0.58–2.33	0.001 **

^*p < 0.05,

^**p < 0.01,

^***p < 0.001.