Table 4.
Demographic characteristics of the four classes, derived from the Latent Class Analysis
| Class 1 Low level of aggression n = 220 |
Class 2 Moderate RA n = 222 |
Class 3 RA& PA n = 97 |
Class 4 Severe RA & PA n = 47 |
Significance (p-value) of between-class comparison | |
|---|---|---|---|---|---|
| Age (M, SD) | 15.8 (2.02) | 15.6 (1.92) | 15.7 (1.74) | 15.1 (1.46) | NS * |
| % Male | 73.6 % | 73.9 % | 68 % | 57.4 % | NS |
| Ethnicity (% non-Caucasian) | 53.6 % | 48.2 % | 51.5 % | 57.4 % | NS |
| IQ (M, SD) | 90.18 (15.65) | 87 (15.34) | 86.33 (14.86) | 89.68 (12.4) | NS |
| Study % * | 1 = 19.8 % 2 = 31.7 % 3 = 51.3 % 4 = 50.5 % | 1 = 51.9 % 2 = 33.2 % 3 = 34.4 % 4 = 34.0 % | 1 = 21.4 % 2 = 18.6 % 3 = 13.6 % 4 = 10.7 % | 1 = 6.9 % 2 = 16.1 % 3 = 0.6 % 4 = 4.9 % | p < 0.001 |
| Between class comparisons (weighted mean scores)** | |||||
| F1: RPQ proactive | 0.09 (0.11) | 0.27 (0.15) | 0.76 (0.16) | 1.27 (0.21) | p < 0.001;1 < 2 < 3 < 4*** |
| F2: RPQ reactive internal frustration | 0.48 (0.28) | 0.99 (0.31) | 1.25 (0.38) | 1.62 (0.32) | p < 0.001; 1 < 2 < 3 < 4*** |
| F3: RPQ reactive external provocation | 0.44 (0.25) | 1.08 (0.30) | 1.51 (0.32) | 1.73 (0.24) | p < 0.001; 1 < 2 < 3 < 4*** |
| Within class comparisons | |||||
| F1 vs. F2 | p < 0.001 | p < 0.001 | p < 0.001 | p < 0.001 | |
| F2 vs. F3 | NS | p < 0.001 | p < 0.001 | NS | |
| F1 vs. F3 | p < 0.001 | p < 0.001 | p < 0.001 | p < 0.001 | |
*NS=Not significant. Study: 1=School in Rotterdam; 2=Closed youth care facility 3=committed crime before the age of 12 and 4=delinquent diversion program
**Weighted mean score = mean of the RPQ factor/total items of the scale
***Also when corrected for age, gender, IQ and ethnicity