A factor analysis of the fagerstrom tolerance questionnaire.

A factor analysis of 1309 Fagerstrom Tolerance Questionnaires (FTQ) was performed with LISCOMP software, which utilizes tetrachoric correlations to account for the dichotomous responses of the FTQ. Three factors with eigenvalues greater than 1.0 were obtained, accounting for 56.6% of the variance. Factor 1 was loaded by questions "How soon on waking do you smoke your first cigarette?," "Do you find it difficult to refrain from smoking in places it is forbidden?," "How many cigarettes a day do you smoke?," and "Do you smoke if you are so ill that you are in bed most of the day?" Factor 2 was loaded by questions "Which cigarette would you hate to give up?" and "Do you smoke more during the morning than during the rest of the day?" Factor 3 was loaded exclusively by question "What brand do you smoke?" The question "Do you inhale always, sometimes, or never?" loaded exclusively on a fourth factor, however its eigenvalue did not reach significance. Support is provided for the modification of the eight-item FTQ to the six-item Fagerstrom Test for Nicotine Dependence (FTND). Based on the wording of the questions that loaded on each factor, we propose that Factor 2 assesses the degree of urgency to initiate smoking after overnight abstinence and that Factor 1 reflects the persistence of smoking during waking hours.