Table 1.
Relative annual change in the prevalence of risk behaviors and unstructured in-person socializing behaviors among U.S. 12th graders (Monitoring the Future survey: 1999–2017).
| Prevalence: 1999 vs. 2017 |
||||||
|---|---|---|---|---|---|---|
| APCa | (95% CI) | Year: 1999 | (95% CI) | Year: 2017 | (95% CI) | |
| Risk Behaviors | ||||||
| Used alcohol (past 30 days) | −2.2% | (−2.4%, −2.0%) | 51.0% | (48.5%, 53.4%) | 34.4% | (32.1%, 36.9%) |
| Used cigarette (past 30 days) | −5.7% | (−6.1%, −5.3%) | 35.3% | (33.0%, 37.6%) | 9.7% | (8.3%, 11.3%) |
| Used cannabis (past 30 days) | 0.3% | (−0.1%, 0.7%) | 24.4% | (22.4%, 26.6%) | 23.6% | (21.6%, 25.7%) |
| Used cocaine (past 30 days) | −6.0% | (−7.4%, −4.5%) | 2.3% | (1.7%, 3.2%) | 0.9% | (0.6%, 1.4%) |
| In physical fight (past year) | −2.1% | (−2.6%, −1.5%) | 14.7% | (13.1%, 16.5%) | 10.5% | (9.0%, 12.1%) |
| Hurt someone on purpose (past year) | −1.6% | (−2.1%, −1.0%) | 13.3% | (11.7%, 15.0%) | 8.6% | (7.3%, 10.1%) |
| Threaten someone with weapon (past year) | −1.8% | (−2.9%, −0.7%) | 3.8% | (3.0%, 4.9%) | 2.6% | (2.0%, 3.6%) |
| Steal something worth <$50 (past year) | −2.3% | (−2.6%, −1.9%) | 31.0% | (28.8%, 33.3%) | 22.6% | (20.6%, 24.8%) |
| Steal something worth ≥$50 (past year) | −2.5% | (−3.2%, −1.9%) | 10.6% | (9.2%, 12.2%) | 7.6% | (6.4%, 9.0%) |
| Unstructured In-Person Socializing b | ||||||
| Go out during the evenings for fun at least 3 times per week (vs. twice per week or less) | −1.8% | (−2.0%, −1.6%) | 51.3% | (48.8%, 53.8%) | 34.8% | (32.4%, 37.3%) |
| Go to parties at least once per month (vs. a few times per year or less) | −1.7% | (−1.8%, −1.5%) | 73.6% | (71.5%, 75.7%) | 52.2% | (49.7%, 54.7%) |
| Ride around in a car just for fun at least once per week (vs. twice per month or less) | −1.3% | (−1.4%, −1.1%) | 64.3% | (62%, 66.6%) | 55.0% | (52.6%, 57.4%) |
| Get together with friends informally “almost every day” (vs. at least once per week or less) | −2.3% | (−2.5%, −2.1%) | 49.5% | (47.1%, 51.9%) | 29.9% | (27.7%, 32.2%) |
a
APC = “Annual Percent Change” (exponentiated coefficient of log-binomial model − 1)*100. APC represents the relative change in the prevalence of a behavior each year (−5% indicates a 5% decline in the prevalence per year, i.e., Relative Risk of 0.95)
b
Dichotomized at approximate 50th percentile of the distribution of the original ordinal variable
Note: All trends statistically significant p<0.05 except for cannabis.