Table 3.

Average Age of Onset and Temporal Ordering of Lifetime Substance Use and Mental Disorders Among CODs by Race/Ethnicity

	White (W) (N=527)		Black (B) (N=277)		Latino (L) (N=200)		Asian (A) (N=46)		Full Sample (N=1050)		Overall Test	Specific Tests
	Estimate	95% CI	Estimate	95% CI	Estimate	95% CI	Estimate	95% CI	Estimate	95% CI
Age of Onset (AOO)
Mean AOO SUD (95% CI)	20.2	[19.7–20.8]	21.8	[20.9–22.8]	20.2	[19.2–21.2]	20.2	[17.9–22.5]	20.4	[19.9–20.8]	0.0016	B>W
Mean AOO MD (95% CI)	17.2	[16.0–18.5]	17.6	[16.1–19.1]	16.3	[14.3–18.4]	14.0	[11.3–16.6]	17.1	[16.1–18.2]	---
Temporal Ordering											---
%SUD Temporally Primary (95% CI)	26.2	[21.3–31.8]	19.2	[14.8–24.5]	27.8	[20.5–36.4]	10.2	[  3.7–24.9]	25.5	[21.6–29.9]
%MD Temporally Primary (95% CI)	56.2	[51.0–61.2]	59.3	[52.5–65.7]	60.8	[51.8–69.2]	72.1	[54.0–85.1]	57.2	[52.9–61.3]
%SUD & MD Contemporaneous (95% CI)	17.6	[14.3–21.4]	21.5	[16.3–27.9]	11.4	[  7.7–16.6]	17.7	[  7.8–35.3]	17.3	[14.6–20.3]

NOTES: Average age of onset is weighted and presented by race/ethnicity. Differences among racial/ethnic groups were tested using regression analysis in which race/ethnicity was dummied and White was used as the reference category. All regression models controlled for gender, age, marital status, income, education, and region. Tests of differences between specific racial/ethnic subgroups groups were only conducted if the overall test of race (joint test of race/ethnicity categories) was significant (p<0.05) and only signficant differences are presented. Cross tabulations were run to produce wieghted temporal ordering prevalence estimates by race/ethnicity. Differences in the probability of MDO primacy by race/ethnicity was tested using logistic regression analysis in which race/ethnicity was dummied and White was used as the reference category; this model controlled for gender, age, marital status, income, education, and region. Tests of differences between specific racial/ethnic subgroups groups were only conducted if the overall test of race (joint test of race/ethnicity categories) was significant (p<0.05) and only signficant

--- Overall test of the effect of race on the likelihood of the co-occurring disorder was not statistically significant.