Table 3.

LCA validators by assigned class membership of ever-daily, past-year smokers (n = 8842).

	Class 1 Low dependence’ (n = 3,477) % or Mean (S.E.)	Class 2 ‘Moderate-behavioral’ (n = 632) % or Mean (S.E.)	Class 3 ‘Physiological dependence’ (n = 3,453) % or Mean (S.E.)	Class 4 High dependence’ (n = 1,280) % or Mean (S.E.)	p-value
Prevalence of Past-Year ND	0.00 (0.00)	71.50 (2.15)	81.57 (0.76)	100.00 (0.00)	<0.0001
Prevalence of Prior to Past-Year ND	10.29 (0.68)	70.72 (2.18)	79.34 (0.82)	95.86 (0.62)	<0.0001
Prevalence of Past-Year MD	6.21 (0.49)	21.43 (2.17)	12.83 (0.72)	29.46 (1.39)	<0.0001
Prevalence of Prior to Past-Year MD	13.80 (0.69)	30.29 (2.30)	24.72 (0.93)	43.01 (1.81)
Mean Age Started Smoking Daily (in years)	20.32 (0.23)	18.51 (0.52)	18.89 (0.17)	17.50 (0.22)	<0.0001
Mean Quantity Smoked When Smoked Daily (in # of cigarettes)	15.18 (0.24)	19.19 (0.60)	17.52 (0.20)	20.98 0.40)	<0.0001
Mean Age of Onset of ND (in years)	34.55 (1.79)	32.38 (1.03)	36.58 (0.41)	31.88 (0.66)	<0.0001