Introduction: This study examined the reliability of self-reported smoking history measures. The key measures of interest were time since completely quitting smoking among former smokers; age at which fairly regular smoking was initiated among former and current smokers; the number of cigarettes smoked per day and the number of years of daily smoking among former smokers; and never smoking. Another goal was to examine sociodemographic factors and interview method as potential predictors of the odds of strict agreement in responses.
Methods: Data from the 2002-2003 Tobacco Use Supplement to the Current Population Survey were examined. Descriptive analysis was performed to detect discrepant data patterns, and intraclass and Pearson correlations and kappa coefficients were used to assess reporting consistency over the 12-month interval. Multiple logistic regression models with replicate weights were built and fitted to identify factors influencing the logit of agreement for each measure of interest.
Results: All measures revealed at least moderate levels of overall agreement. However, upon closer examination, a few measures also showed some considerable differences in absolute value. The highest percentage of these differences was observed for former smokers' reports of the number of years smoking every day.
Conclusions: Overall, the data suggest that self-reported smoking history characteristics are reliable. The logit of agreement over a 12-month period is shown to depend on a few sociodemographic characteristics as well as their interactions with each other and with interview method.