A multiple motive/multi-dimensional approach to measure smokeless tobacco dependence

Background: Unlike various research studies conducted to address dependence among smokers, only a few studies have examined smokeless tobacco (ST) dependence. The Fagerstrom Tolerance Questionnaire (FTQ) and Fagerstrom Test for Nicotine Dependence (FTND) based scales are the most widely used measures of nicotine dependence for both ST users and smokers. These scales were initially developed to measure physical dependence and tolerance and not to assess other salient dimensions of dependence such as craving, compulsion, or withdrawal, as defined by DSM-IV and ICD-10. The aim of this study is to develop and validate a multidimensional scale that has better content coverage, factor structure, and psychometric properties to measure dependence among ST users. Methods: 100 adult male smokeless tobacco users were recruited through email distribution lists and community referral. Participants completed three different nicotine dependence questionnaires and provided information related to their tobacco use and demographic characteristics. They also provided a saliva sample for cotinine measurement. In order to develop the new ST scale, subscales and items were selected based on correlation and factor analysis of the modified WISDM-68. Reliability and validity of the new scale, Oklahoma Scale for Smokeless Tobacco Dependence (OSSTD) were also assessed. Results: The new ST scale identified seven latent constructs including 23 items to measure ST dependence. Internal consistency as measured by Cronbach's coefficient (alpha = 0.925) indicated better reliability of OSSTD than FTND-ST. Concurrent validity of OSSTD as evaluated by comparing it with dependence diagnosis and FTND-ST was affirmative. There was a significant correlation between the OSSTD total score and the cotinine levels and tobacco use characteristics among study participants. Conclusion: OSSTD possesses better psychometric properties and provides an effective and efficient tool to measure ST dependence as a multidimensional construct. (C) 2013 Elsevier Ltd. All rights reserved.