Abstract
OBJECTIVE: Studying adolescent-onset brief depressive spells, we saw a chance to adapt a cross-cohort approach for successive cross-sectionally gathered epidemiological estimates on birth cohorts. METHODS: The United States (US) study population estimates are for noninstitutionalized community-dwelling 17- to 18-year-olds, sampled, recruited, and assessed using audio computer assisted self-interviews for the National Surveys on Drug Use and Health each year, 2008-2016. Estimated age and year-specific lifetime history cumulative incidence proportions are presented, with 95% confidence intervals, as well as age-specific meta-analysis summary estimates. RESULTS: Occurrence of a brief depressive spell (BDS) among the 2008 U.S. 17-year-olds showed a surprising difference with the 2009 statistically independent sample of that same "birth cohort" assessed at age 18 years. "Negative growth" was seen instead of an expected increase in those affected. Independent replication estimates of this BDS negative growth difference were seen in multiple successive birth cohorts. CONCLUSIONS: This well-replicated difference in BDS estimates offers a fascinating puzzle to be solved with focused inquiry. The puzzle's solution is important because National Surveys on Drug Use and Health does not assess Major Depression unless a BDS lifetime history is ascertained.