Development and psychometric properties of the smoking restraint questionnaire

Restraint is a component of self-control that focuses on the deliberate reduction of an undesired behaviour and is theorised to play a role in smoking reduction and cessation. However, there exists no instrument to assess smoking restraint. The current research was conducted in two parts. First, a literature review summarised the nature of smoking and its relationship with restraint. Second, the Smoking Restraint Questionnaire (SRQ) was developed and tested on a large sample of smokers. Participants were 406 smokers (48% female; 52.2% non-daily) with a mean age of 38.83 years (SD = 12.05). After completing a baseline questionnaire designed to assess smoking restraint, they also completed 21-days of ecological momentary assessment (EMA). During EMA they recorded each cigarette smoked and answered questions related to planned restraint every morning and restraint attempts every evening. The 4-item SRQ was found to fit a single factor (RMSEA = .038, CFI = .99, TLI = .99) and was internally consistent (composite reliability = .74). The questionnaire assesses the setting of weekly restraint goals and attempts at not lighting up when tempted to smoke. Participant SRQ scores related positively to EMA data on plans to restrain (p < .001) and frequency of restraint attempts (p < .001). The SRQ is promising as a measure of smoking restraint and may enable further research and insights into smoking reduction and cessation.