Misclassification of smoking status by self-reported cigarette consumption

Area of Science:

• Epidemiology
• Biochemistry
• Public Health

Background:

• Accurate smoking status assessment is vital for understanding tobacco-related health risks.
• Self-reported data may be subject to misclassification, impacting study validity.
• Biochemical markers offer a more objective measure of tobacco exposure.

Purpose of the Study:

• To evaluate the extent of misclassification between self-reported smoking and serum cotinine levels.
• To determine the reliability of self-reported cigarette consumption in Mexican American adults.
• To highlight the importance of biochemical verification in smoking status assessment.

Main Methods:

• Compared self-reported cigarette consumption with serum cotinine levels in 743 Mexican American participants.
• Defined biochemical smokers using a serum cotinine threshold of ≥0.084 microM/L (14 ng/ml).
• Analyzed discrepancies between self-reported and biochemical smoking status.

Main Results:

• 6.3% of self-reported nonsmokers were classified as biochemical smokers.
• 12.1% of self-reported smokers had cotinine levels below the biochemical smoker threshold.
• Misclassification was observed in both self-reported smokers and nonsmokers, indicating potential under- or overestimation of smoking prevalence.

Conclusions:

• Self-reported cigarette consumption alone may be insufficient for accurately assessing tobacco use risks.
• Serum cotinine measurement is important for quantifying misclassification in smoking status.
• Biochemical verification enhances the accuracy of epidemiologic studies on tobacco use.