Table 1.

Demographic and Rating Scale Variables for the Overall Study Sample and Subgroups based on Smoking Status

Variable	Study Sample (n = 105)	Smoker Subgroup (n = 58)	Non-Smoker Subgroup (n = 47)
Age	38.1 (± 12.8)	38.7 (± 13.4)	37.4 (± 12.1)
Gender (% Female)	40	36	45
Ethnicity (% Caucasian)	51	48	55
Education (years)	14.7 (± 2.1)	14.4 (± 2.1)	15.1 (± 2.1)
Cigarettes per day	N/A	18.7 (± 4.2)	N/A
Caffeine (coffee cup equivalents) per day	1.3 (± 1.5)	1.6 (± 1.6)	1.0 (± 1.3)
Alcoholic Beverages per week	2.3 (± 3.3)	2.8 (± 4.1)	1.7 (± 2.0)
HAM-A Rating Scale Score	2.1 (± 2.3)	2.2 (± 2.4)	2.0 (± 2.2)
HAM-D Rating Scale Score	1.8 (± 2.1)	2.0 (± 2.2)	1.6 (± 2.0)

The smoker and non-smoker subgroups did not differ significantly in any of the variables listed (unpaired t or chi-square tests nonsignificant) other than cigarettes per day. HAM-A = Hamilton Anxiety Rating Scale. HAM-D = Hamilton Depression Rating Scale.