Introduction: The 68-item Wisconsin Inventory of Smoking Dependence Motives (WISDM-68) is a theoretically derived measure of tobacco dependence consisting of 13 subscales measuring a variety of smoking motives. The WISDM-68 subscales have demonstrated good psychometric characteristics and have the potential to elucidate diverse nicotine dependence factors and mechanisms. The present research aimed to shorten the WISDM to reduce assessment burden while maintaining or enhancing its psychometric properties.
Methods: Data from three independent samples (one longitudinal observational study and two randomized clinical trials) were used to select subscales and reduced sets of items in order to develop and test a brief version of the WISDM-68. The full-item and reduced-item versions of the WISDM were then compared in terms of reliability, validity, and model fit (via confirmatory factor analysis) in the three independent samples.
Results: Thirty-one items were dropped from the WISDM, the Behavioral Choice-Melioration subscale was dropped, and the Negative and Positive Reinforcement subscales were consolidated. This resulted in a new WISDM short form (Brief WISDM) comprising 37 items that load onto 11 subscales. The psychometric properties of the reduced-item WISDM subscales were found to be comparable with the full-item subscales in terms of internal consistency, long-term stability, concurrent validity, predictive validity, and model fit.
Discussion: These analyses provide good evidence that the 37-item Brief WISDM can be used in place of the original 68-item WISDM if researchers desire to reduce participant assessment burden.