Other substance use secondary outcomes (24-month follow-up)
| Outcome | ICC* | Proportion of events in control arm (%) | Proportion of events in SFP arm (%) | Adjusted OR | 95% CI | P value | ||
| Lower limit | Upper limit | |||||||
| Alcohol-related problems in the last 12 months | 0.18 | 51/326 (15.6) | 60/384 (15.6) | 0.95 | 0.59 | 1.54 | 0.849 | |
| Currently smoke at least one cigarette a week | 0.41 | 52/347 (15.0) | 59/402 (14.7) | 0.94 | 0.53 | 1.66 | 0.828 | |
| Ever taken cannabis | 46/338 (13.6) | 58/393 (14.8) | 1.21 | 0.57 | 2.55 | 0.617 | ||
| Taken cannabis at least once in the last 12 months | 0.43 | 41/337 (12.2) | 49/393 (12.5) | 1.01 | 0.51 | 1.97 | 0.985 | |
| Taken cannabis at least once in the last 30 days | 20/338 (5.9) | 21/393 (5.3) | 0.77 | 0.36 | 1.68 | 0.518 | ||
| Time to alcohol initiation† | 88/246 (35.8) | 81/273 (29.7) | 0.86 | 0.64 | 1.17 | 0.344 | ||
| Frequency of consuming 5+ drinks in a row in the last 30 days‡ | 0 | 0.00 | 315/345 (91.3) | 348/401 (86.8) | 1.55 | 0.95 | 2.51 | 0.080 |
| 1–2 | 15/345 (4.3) | 36/401 (9.0) | ||||||
| 3–5 | 15/345 (4.8) | 17/401 (4.2) | ||||||
| Frequency of drinking beer‡ | Never | 0.00 | 290/346 (83.8) | 331/401 (82.5) | 1.15 | 0.77 | 1.72 | 0.492 |
| Rarely | 20/346 (5.8) | 17/401 (4.2) | ||||||
| Every month | 26/346 (7.5) | 36/401 (9.0) | ||||||
| At least once a week | 10/346 (2.9) | 17/401 (4.2) | ||||||
| Frequency of drinking wine‡ | Never | 0.00 | 323/345 (93.6) | 375/402 (93.3) | 1.06 | 0.59 | 1.92 | 0.837 |
| Rarely | 5/345 (1.4) | 7/402 (1.7) | ||||||
| At least once a month | 17/345 (4.9) | 20/402 (5.0) | ||||||
| Frequency of drinking spirits‡ | Never | 0.71 | 298/346 (86.1) | 351/401 (87.5) | 0.85 | 0.50 | 1.46 | 0.567 |
| Rarely | 15/346 (4.3) | 13/401 (3.2) | ||||||
| Every month | 21/346 (6.1) | 24/401 (6.0) | ||||||
| At least once a week | 12/346 (3.5) | 13/401 (3.2) | ||||||
| Frequency of drinking alcopops‡ | Never | 0.35 | 303/346 (87.6) | 345/402 (85.8) | 1.24 | 0.78 | 1.97 | 0.361 |
| Rarely | 19/346 (5.5) | 17/402 (4.2) | ||||||
| At least once a month | 24/346 (6.9) | 40/402 (10.0) | ||||||
| Frequency of drinking cider‡ | Never | 0.00 | 305/346 (88.2) | 346/402 (86.1) | 1.26 | 0.80 | 1.97 | 0.313 |
| Rarely | 12/346 (3.5) | 13/402 (3.2) | ||||||
| At least once a month | 29/346 (8.4) | 43/402 (10.7) | ||||||
*Calculated using the standard π2/3 estimator for binary outcomes.
†Single-level Cox regression; percentage of young people who initiated alcohol after baseline; adjusted HR.
‡Multilevel ordinal regression—not consuming 5+ drinks in a row and never drunk anything alcoholic were the reference categories.
ICC, intracluster correlation coefficient; SFP, Strengthening Families Programme.