Demographic Variables and Test Scores by Age Group
| Variable | 9–12 Years (n = 26) | 13–14 Years(n = 74) | 15–16 Years(n = 100) | 17–18 Years(n = 47) | F | p | |
|---|---|---|---|---|---|---|---|
| Grade | M | 5.0 | 7.3 | 8.7 | 10.0 | 142.1 | .001 |
| SD | 1.2 | 1.0 | 1.0 | 1.1 | |||
| Estimated IQ | M | 73.7 | 74.3 | 72.6 | 87.6 | 11.7 | .001 |
| SD | 14.1 | 15.5 | 15.7 | 12.4 | |||
| WRAT | |||||||
| Read | M | 73.0 | 81.6 | 82.7 | 83.4 | 2.7 | .05 |
| SD | 21.9 | 15.1 | 15.7 | 16.4 | |||
| Spell | M | 78.6 | 82.3 | 84.4 | 83.9 | 1.0 | .40 |
| SD | 19.4 | 16.5 | 15.4 | 16.2 | |||
| Arith* | M | 77.2 | 80.0 | 83.0 | 85.4 | 2.9 | .03 |
| SD | 14.5 | 13.8 | 11.3 | 15.2 | |||
| BPRS-C | |||||||
| Internal† | M | 6.14 | 5.97 | 5.80 | 6.14 | .53 | .66 |
| SD | 8.4 | 6.6 | 6.1 | 8.0 | |||
| External‡ | M | 5.01 | 4.05 | 4.09 | 3.82 | 6.95 | .001 |
| SD | 1.58 | 1.06 | 1.07 | .91 | |||
| DevMal§ | M | 7.31 | 6.81 | 6.65 | 6.47 | 1.41 | .24 |
| SD | 2.08 | 1.96 | 1.72 | 1.53 | |||
| Number of charges | M | 9.1 | 14.5 | 17.7 | 18.7 | 4.9 | .003 |
| SD | 6.2 | 11.1 | 13.0 | 12.3 |
Data are the mean (M) ± SD.
* Arithmetic subtest of the WRAT-3.
† Internalization factor of the BPRS-C.
‡ Externalization factor of the BPRS-C.
§ Developmental maladjustment factor of the BPRS-C.