Validity of the E-Cigarette Wisconsin Inventory of Smoking Dependence Motives (e-WISDM) in Exclusive E-Cigarette Users: Evidence from a Laboratory Self-Administration Study.

Introduction: Prior research suggests that the e-Cigarette Wisconsin Inventory of Smoking Dependence Motives (e-WISDM) distinguishes primary (e-PDM) and secondary dependence (e-SDM), however, there is little research on these e-WISDM dimensions and prior research comprised dual users (using cigarettes and e-cigarettes) and those using older generations of e-cigarettes.

Methods: Those exclusively using contemporary e-cigarettes (N = 164) completed the e-WISDM and a laboratory self-administration session and rated pre-use expectancies and post-use experiences.

Results: Only a 1-factor model limited to the primary scales (Automaticity, Tolerance, Craving, Loss of Control) achieved good model fit. The e-PDM was correlated with the Penn State Electronic Cigarette Dependence Index (PS-ECDI), r = .79, p < .001. The e-PDM and PS-ECDI were similarly correlated with use topography and self-reported measures. Analyses of motive profiles identified Taste, Tolerance, and Automaticity as the most strongly endorsed motives in the full sample. Subgroup analyses indicated primary motives were more elevated in in daily vs. non-daily e-cigarette users and participants with vs. without a history of smoking cigarettes. Taste motives were stronger in users of 3rd vs. 4th generation e-cigarettes.

Conclusions: These findings suggest that the four e-PDM subscales are a concise, reliable, and valid measure of core e-cigarette dependence motives that are related to meaningful dependence attributes.

Implications: Electronic cigarettes (e-cigarettes) are dependence-producing. Instruments that measure e-cigarette dependence are necessary to identify users who may have difficulty quitting e-cigarettes and who are at risk for use-related harms. The four subscales of the e-WISDM PDM index self-reported heavy e-cigarette use, craving, automatic or mindless use, and perceived loss of control over use. The current research supports the validity of the e-WISDM PDM as a measure of core e-cigarette dependence in users of today's e-cigarette devices.