Responsiveness of the smoking cessation quality of life (SCQoL) questionnaire

Background: The Smoking Cessation Quality of Life (SCQoL) questionnaire was developed to quantify changes in self-reported functioning and well-being associated with the smoking cessation process and to facilitate comparisons among smokers, former smokers, and nonsmokers. The SCQoL includes 5 cessation-targeted scales and the 8 multi-item scales of the Medical Outcomes Study 36-Item Short-Form Health Survey. Objective: This study was conducted to assess the responsiveness of the SCQoL by analyzing associations between SCQoL scale scores and duration of smoking abstinence. Methods: The SCQoL was administered at a screening visit and 2 to 6 weeks after screening as part of a longitudinal study. Study participants included smokers who intended to quit smoking. Subjects were required to purchase nicotine inhalers and were prompted to quit smoking before follow-up. Based on self-reported duration of abstinence at follow-up, subjects were categorized as recidivists (0 days smoke free), short-term abstainers (1-7 days smoke free), or longer-term abstainers (>7 days smoke free). Kruskal-Wallis tests were used to compare changes in scale scores from screening to follow-up among the 3 groups. Results: The internal consistency reliability of the 13 SCQoL scales ranged from 0.67 to 0.92. Subjects who maintained abstinence for longer periods experienced smaller declines in health-related quality of life between the screening and follow-up assessments. Differences among the 3 groups were driven primarily by differences between recidivists and longer-term abstainers. Conclusion: The results are consistent with research indicating that recidivists report a greater number of (and more severe) cessation-related symptoms than abstainers. The findings of this investigation provide evidence for the responsiveness of the SCQoL.