Underreporting of past-year cannabis use on a national survey by people who smoke blunts

Abstract

Background: Accurate prevalence estimates are critical to epidemiological research but discordant responses on self-report surveys can lead to over- or underestimation of drug use. We sought to examine the extent and nature of underreported cannabis use (among those later reporting blunt use) from a national drug survey in the US. Methods: We used data from the 2015–2019 National Survey on Drug Use and Health (N = 281,650), a nationally representative probability sample of non-institutionalized populations in the US. We compared self-reported prevalence of past-year cannabis use and blunt use and delineated correlates of underreporting cannabis use, defined as reporting blunt use but not overall cannabis use. Results: An estimated 4.8% (95% CI: 4.4–5.2) of people reported blunt use but not cannabis use. Although corrected prevalence, cannabis use recoded as use only increased from 15.2% (95% CI: 15.0–15.4) to 15.5% (95% CI: 15.3–15.7), individuals who are aged ≥50 (aOR = 1.81, 95% CI: 1.06–3.08), female (aOR = 1.35, 95% CI: 1.12–1.62), Non-Hispanic Black (aOR = 1.43, 95% CI: 1.16–1.76), or report lower English proficiency (aOR = 3.32, 95% CI: 1.40–7.83) are at increased odds for providing such a discordant response. Individuals with a college degree (aOR = 0.57, 95% CI: 0.39–0.84) and those reporting past-year use of tobacco (aOR = 0.75, 95% CI: 0.62–0.91), alcohol (aOR = 0.42, 95% CI: 0.33–0.54), cocaine (aOR = 0.50, 95% CI: 0.34–0.73), or LSD (aOR = 0.52, 95% CI: 0.31–0.87) were at lower odds of providing a discordant response. Conclusion: Although changes in prevalence are small when correcting for discordant responses, results provide insight into subgroups that may be more likely to underreport use on surveys.

Keywords:

• Marijuana
• national surveys
• survey reliability

Disclosure statement

One author has consulted for Alkermes. The authors have no other potential conflicts to declare.

Author contributions

All authors are responsible for this reported research. A. Le and J. Palamar conceptualized and designed the study. J. Palamar conducted the statistical analyses. All authors contributed to the drafting of the initial manuscript, interpreted results, and critically reviewed and revised the manuscript. All authors approved the final manuscript as submitted.

Additional information

Funding

This project was funded by the National Institutes of Health [R01DA044207 and K23DA043651]. The funding organization had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.