title: A review of the validity and reliability of smokeless tobacco dependence measures.
abstract: BACKGROUND
  With the growing marketing of alternate tobacco products, advocacy of harm reduction, and smoke free air policies, an overall increase in Smokeless Tobacco (ST) use has been observed since the 1970s. Numerous studies have been published addressing nicotine dependence measures for smokers; however, research in the field of ST dependence measures is scarce.
  
  
  OBJECTIVE
  The aim of this study is to summarize the psychometric properties of ST dependence measures by evaluating the reliability and validity of these scales through peer review research.
  
  
  METHODS
  A systematic literature search was conducted within the databases of PubMed and OVID Medline. Four publications reporting on the psychometric properties of ST dependence measures were identified; two regarding FTQ based scales, one regarding an FTND based scale, and one comparing two of these modified scales. A predefined set of criteria was used to assess the psychometric properties of these measures.
  
  
  RESULTS
  ST dependence measures depend heavily on two underlying factors, heaviness of tobacco use and withdrawal. The internal consistency of the measures was low to moderate, Cronbach's α ranging from 0.30 to 0.52 Cotinine was used as criterion variable to validate the results of the dependence measures. Concurrent validity against DIS-IV-ND based diagnosis was not established for modified FTQ scale. Predictive validity of these ST dependence scales was measured as abstinence of ST use at three and six months. FTQ-ST was predictive of abstinence at three months however failed to predict six months abstinence.
  
  
  CONCLUSIONS
  FTQ and FTND based measures have inherited shortcomings and have limited psychometric properties. With ease of use and wide application in tobacco research, these measures provide preliminary foundation for studying ST dependence. However, the complexity of tobacco dependence requires a multidimensional measure with high validity and reliability for effective prevention care and for research purposes.
authors.affiliation: Department of Biostatistics and Epidemiology, University of Oklahoma Health Sciences Center, 801 NE 13th Street, CHB-309, Oklahoma City, OK 73104, USA. Nasir-Mushtaq@ouhsc.edu
authors.forename: Nasir
authors.initials: N
authors.lastname: Mushtaq
authors.forename: Laura A
authors.initials: LA
authors.lastname: Beebe
mesh_terms: D006801:Humans; D011569:Psychiatric Status Rating Scales / Q000592:standards*; D011594:Psychometrics; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards; D014029:Tobacco Use Disorder / Q000175:diagnosis*; D014030:Tobacco, Smokeless