Citation
Rosenbaum, Janet E (2024). Substance Use and College Completion Among Two-Year and Four-Year College Students From a Nationally Representative Longitudinal Study. Cureus. vol. 16 (5)Abstract
Young adults from disadvantaged populations access higher education through two-year colleges, butsubstance use research among young adults focuses on four-year colleges. Filling this research gap is
important given recent policy changes that have increased marijuana availability for young adults. This
study uses a subsample of college-enrolled participants from the National Longitudinal Study of Adolescent
to Adult Health (Add Health) to evaluate whether substance use predicts educational attainment seven years
later, comparing 888 students attending a two-year college with 1,398 matched students attending a fouryear college. Matched students were identified using a propensity score method so that students were
comparable on 15 measures, including precollege grades, precollege test scores, and precollege substance
use. Compared with similar four-year college students, two-year college students were more likely to use
methamphetamines, cocaine, or marijuana; more likely to report problematic substance use; and less likely
to use alcohol. Two-year college students who used methamphetamines in the past year (incidence rate
ratio (IRR) = 1.51, 95% CI (1.12, 2.04), p = 0.007) or past month (IRR = 1.69, 95% CI (1.09, 2.61), p = 0.02) or
completed alcohol abuse treatment (IRR = 1.58, 95% CI (1.21, 2.07), p < 0.001) were less likely to complete
college than two-year college students without those risk factors. Among the matched four-year college
students, students who reported that drugs interfered with school or work in the past year (IRR = 1.84 (1.28,
2.64), p = 0.001), used cocaine in the past year (IRR = 1.47 (1.04, 2.08), p = 0.03), and used marijuana in the
past year (IRR = 1.30 (1.07, 1.57), p = 0.007), past month (IRR = 1.31 (1.07, 1.61), p = 0.01), or ≥5 times in the
past month (IRR = 1.44 (1.12, 1.85) p = 0.005) were less likely to complete college than the matched four-year
college students without those risk factors. Substance use interventions should target both two-year and
four-year college students. Two-year colleges that better accommodate students who complete substance
use treatment may improve these students’ completion. Students who use marijuana or cocaine or whose
drug use impairs functioning may benefit from an incremental approach of completing a two-yea