The validity of self-reported smoking: A review and meta-analysis

Objectives. The purpose of this study was to identify circumstances in which biochemical assessments of smoking produce systematically higher or lower estimates of smoking than self-reports. A secondary aim was to evaluate different statistical approaches to analyzing variation in validity estimates. Methods. Literature searches and personal inquiries identified 26 published reports containing 51 comparisons between self-reported behavior and biochemical measures. The sensitivity and specificity of self-reports of smoking were calculated for each study as measures of accuracy. Results. Sensitivity ranged from 6% to 100% (mean = 87.5%), and specificity ranged from 33% to 100% (mean = 89.2%). Interviewer-administered questionnaires, observational studies, reports by adults, and biochemical validation with cotinine-plasma were associated with higher estimates of sensitivity and specificity. Conclusions. Self-reports of smoking are accurate in most studies. To improve accuracy, biochemical assessment, preferably with cotinine-plasma, should be considered in intervention studies and student populations.