Objectives: This study compared serum cotinine and thiocyanate in assessment of self-reported smoking behavior among 1400 men and 1809 women from two New England communities.
Methods: Serum thiocyanate and serum cotinine levels were analyzed on 2411 and 798 survey respondents, respectively, in an attempt to provide an objective measurement for validation of self-reported smoking behaviors that were obtained through an in-home interviewer-administered questionnaire. Cross-sectional household surveys were conducted with randomly selected men and women, aged 18-65, between 1981 and 1993 as part of the evaluation of the Pawtucket Heart Health Program.
Results: Among smokers, the thiocyanate test had similar rates of agreement for women(88.0%) and for men (89.3%). However, among nonsmokers, thiocyanate had higher rates of agreement for women (91.5%) than for men (85.2%). For cotinine, the rates of agreement among smokers were higher for women (91.6%) than for men (89.7%). Similarly, the rates of agreement among nonsmokers were also higher for women (93.9%) than for men (91.9%). Overall,serum cotinine had a higher concordance rate than serum thiocyanate for both men and women.
Conclusions: Although our results suggested that there were some differences in self-reporting of smoking status by gender, results were quite similar between self-reports of smoking and both biochemical tests. The results obtained from this large population-based study from two New England communities lend credibility to the use of self-reports as a low-cost accurate approach to obtaining information on smoking behaviors among both men and women in large population-based health surveys.