Frequencies and crude ORs for demographic, risk and protective factors for gang affiliation (N=4131)
| Variable | Total N (%) | Gang-affiliated students (N=294) | |
| N (%) | Crude OR (95% CI) | ||
| Demographic factors | |||
| Age | |||
| 12–13 years | 1222 (29.58) | 95 (7.77) | Referent |
| 14–15 years | 1180 (28.56) | 105 (8.90) | 1.16 (0.72 to 1.88) |
| 16 years or older | 1705 (41.27) | 92 (5.40) | 0.68 (0.38 to 1.22) |
| Missing | 24 (0.58) | 2 (8.33) | 1.08 (0.25 to 4.62) |
| Sex | |||
| Female | 2127 (51.49) | 113 (5.31) | Referent |
| Male | 1982 (47.98) | 179 (9.03) | 1.77 (1.37 to 2.28) |
| Missing | 22 (0.53) | 2 (9.09) | 1.78 (0.38 to 8.47) |
| Race/ethnicity | |||
| White, non-Hispanic | 922 (22.32) | 43 (4.66) | Referent |
| African American, non-Hispanic | 935 (22.63) | 88 (9.41) | 2.12 (1.21 to 3.73) |
| Hispanic | 1809 (43.79) | 128 (7.08) | 1.56 (1.05 to 2.31) |
| Others, non-Hispanic | 416 (10.07) | 33 (7.93) | 1.76 (1.08 to 2.86) |
| Missing | 49 (1.19) | 2 (4.08) | 0.87 (0.21 to 3.57) |
| Potential risk factors | |||
| Depressed mood† | |||
| No | 2464 (59.65) | 154 (6.25) | Referent |
| Yes | 1667 (40.35) | 140 (8.40) | 1.43 (1.07 to 1.92) |
| Suicidal ideation | |||
| No | 3416 (82.69) | 210 (6.15) | Referent |
| Yes | 715 (17.31) | 84 (11.75) | 2.03 (1.62 to 2.55) |
| Alcohol use | |||
| Never | 2009 (48.63) | 81 (4.03) | Referent |
| Once a year to once a month | 1273 (30.82) | 83 (6.52) | 1.66 (1.11 to 2.47) |
| 2–3 days a month | 328 (7.94) | 35 (10.67) | 2.84 (1.76 to 4.58) |
| 1–2 days a week or more | 391 (9.47) | 84 (21.48) | 6.51 (4.64 to 9.15) |
| Missing | 130 (3.15) | 11 (8.46) | 2.20 (0.88 to 5.52) |
| Drug use | |||
| Never | 3090 (74.80) | 139 (4.50) | Referent |
| Once a year to once a month | 409 (9.90) | 41 (10.02) | 2.37 (1.50 to 3.74) |
| 2–3 days a month | 130 (3.15) | 17 (13.08) | 3.19 (1.84 to 5.56) |
| 1–2 days a week or more | 409 (9.90) | 84 (20.54) | 5.49 (3.68 to 8.17) |
| Missing | 93 (2.25) | 13 (13.98) | 3.45 (1.79 to 6.64) |
| Delinquency | |||
| Never | 1503 (36.38) | 29 (1.93) | Referent |
| 1–3 times | 1478 (35.78) | 80 (5.41) | 2.91 (1.53 to 5.52) |
| 4–9 times | 447 (10.82) | 56 (12.53) | 7.28 (4.38 to 12.10) |
| 10 or more times | 645 (15.61) | 127 (19.69) | 12.46 (7.38 to 21.05) |
| Missing | 58 (1.40) | 2 (3.48) | 1.82 (0.40 to 8.17) |
| Peer victimisation | |||
| No | 1880 (45.51) | 114 (7.45) | Referent |
| Yes | 2251 (54.49) | 180 (8.00) | 1.35 (1.04 to 1.74) |
| Potential protective factors | |||
| Coping skills | |||
| Low level of confidence | 1475 (35.71) | 197 (13.36) | Referent |
| Moderate level of confidence | 1472 (35.63) | 75 (5.10) | 0.35 (0.27 to 0.44) |
| High level of confidence | 1184 (28.66) | 22 (1.86) | 0.12 (0.08 to 0.19) |
| Peer support | |||
| No | 2050 (49.62) | 173 (8.44) | Referent |
| Yes | 2081 (50.38) | 121 (5.81) | 0.67 (0.52 to 0.86) |
| Parental positive reinforcement | |||
| No | 1527 (36.96) | 130 (8.51) | Referent |
| Yes | 2604 (63.04) | 164 (6.30) | 0.72 (0.56 to 0.93) |
| Parental monitoring | |||
| Low level | 1480 (35.83) | 175 (11.82) | Referent |
| Moderate level | 1332 (32.24) | 75 (5.63) | 0.44 (0.36 to 0.55) |
| High level | 1319 (31.93) | 44 (3.34) | 0.26 (0.20 to 0.33) |
| Family support | |||
| No | 1823 (44.13) | 173 (9.49) | Referent |
| Yes | 2308 (55.87) | 121 (5.24) | 0.53 (0.41 to 0.68) |
| Adult support at school | |||
| No | 268 (6.49) | 33 (12.31) | Referent |
| Yes | 3863 (93.51) | 261 (6.76) | 0.52 (0.28 to 0.96) |
| School connectedness | |||
| No | 867 (20.99) | 75 (8.65) | Referent |
| Yes | 3264 (79.01) | 219 (6.71) | 0.76 (0.62 to 0.92) |
↵† The missing response category was added to the referent group for all dichotomous variables and variables divided by tertiles.