Table 1.
Descriptive statistics of participant-level variables.
| Variable | Mean | SD | Range | Skewness | Kurtosis |
|---|---|---|---|---|---|
| Age | 18.49 | 0.55 | 16–20 | 0.49 | 1.68 |
| Total GMV | 0.67 | 0.06 | 0.53–0.82 | 0.10 | −0.51 |
| CNCEE | 521.32 | 70.13 | 301–645 | −0.46 | 0.06 |
| Term examination | 544.38 | 45.61 | 401–633 | −0.51 | 0.11 |
| RAPM | 24.16 | 5.64 | 6–36 | −0.28 | 0.01 |
| Family SES | 5.29 | 1.49 | 1–9 | −0.14 | −0.15 |
Note: SD = standard deviation; GMV = gray matter volume; CNCEE = Chinese National College Entrance Examination; RAPM = Raven’s Advanced Progressive Matrix; SES = socioeconomic status. The values of term examination were based on 129 participants, other values were based on 214 participants.