Abstinence expectancies and quit attempts.

INTRODUCTION: Several scales have been developed to measure expectancies about smoking cessation. This secondary analysis tested the reliability and validity of one of the most commonly used expectancy measures - the Perceived Risks and Benefits of Quitting Scale (PRBQ).

METHODS: Smokers (n=143) who planned to quit at some point in the next 3months entered an observational study in which they called an Interactive Voice Response system nightly for 3months to report quit attempts and abstinence. They completed the PRBQ at baseline and the end of 1, 2 and 3months. No treatment was provided.

RESULTS: The Risks scores and Benefit scores of the PRBQ had high internal reliability (alpha=0.88-0.96 across administrations) and high test-retest stability (ICC=0.67-0.80), but poor to moderate concurrent validity (correlation with other cessation measures=0.09-0.52), and poor predictive validity (no significant prediction of quit attempts or duration of abstinence). Results were similar for men and women.

CONCLUSIONS: The PRBQ appears to be reliable but, similar to other scales of cessation expectancies, its validity appears to be poor. The face valid notion that expectations influence quitting requires further testing.