Table 3: Association between age at first use of alcohol and likelihood of heavy alcohol use in the last 30 days among subsample with low Kessler score and good, very good, or excellent self-rated physical health.

Age at first use of alcoholIRR(95% conf. interval)IRR*(95% conf. interval)

Age group 18–29
<123.302.74–3.983.192.62–3.88
12–143.362.98–3.783.352.95–3.80
15–172.442.19–2.722.472.20–2.76
18–241.001.00
≥250.180.06–0.510.190.06–0.55

Age group 30–49
<122.662.04–3.452.541.89–3.42
12–142.061.68–2.532.031.63–2.52
15–171.601.32–1.941.601.30–1.96
18–241.001.00
≥250.400.26–0.610.430.27–0.68

IRR: incidence rate ratios.
Models controlled for all variables showed in Table 2.
*Estimations from subsample with Kessler scores of 12 or less and a self-rating of health as good, very good, or excellent.