. Author manuscript; available in PMC: 2014 Nov 24.

Published in final edited form as: Addict Behav. 2012 Oct 29;38(3):1757–1763. doi: 10.1016/j.addbeh.2012.10.013

Table 4.

Initial factor loadings, eigenvalues, and variance explained in the principal component analyses for the FTND-R and FTND.

Item	Factor 1	Factor 2
FTND-R
1. Cigarettes per day	.44	.53
2. Smoke more first 2 hours of day	.65	.21
3.Time to 1^st cigarette	.67	.42
4. Cigarette most hate to give up	.76	−.12
5. Difficult to refrain	−.11	.79
6. Smoke when ill	.28	.72
Eigenvalue	2.38	1.02
Percent Variance (total = 56.66%)	39.73%	16.92%
FTND
1. Cigarettes per day	.46	.54
2. Smoke more first 2 hours of day	.63	.14
3. Time to 1^st cigarette	.68	.43
4. Cigarette most hate to give up	.75	−.13
5. Difficult to refrain	−.11	.76
6. Smoke when ill	.20	.66
Eigenvalue	2.18	1.02
Percent Variance (total = 53.37%)	36.30%	17.06%

Note. N = 343, FTND-R = Fagerström Test of Nicotine Dependence-Revised, FTND = Fagerström Test of Nicotine Dependence.