Table 3 Classical test theory statistics, convergent validity, and predictive validity
Subscale | Items | Classical test theory statistics (N = 285) | Correlation with comparator instruments | Correlation with future WPPSI raw IQb (N = 52) | ||||
|---|---|---|---|---|---|---|---|---|
Cronbach’s α | Item-rest correlations | Mean (SD) item score, 0–4 scale | Comparator instrument | N | Correlation coefficient (r) | Correlation coefficient (r) | ||
Child-focused | ||||||||
Harsh discipline and abuse | 10 | 0.85 | 0.23–0.82 | 0.73 (0.69) | HOME-Aa | 106 | −0.35† | −0.29* |
Neglect | 3 | 0.71 | 0.39–0.63 | 0.43 (0.60) | HOME-Oa | 106 | −0.27** | −0.34* |
Caregiver emotional unavailability | 5 | 0.88 | 0.54–0.83 | 1.81 (1.08) | HOME-Ea | 106 | −0.03 | −0.43** |
Maternal-focused | ||||||||
Depression | 8 | 0.95 | 0.75–0.84 | 0.99 (0.90) | EPDS | 185 | 0.41† | −0.43** |
Social isolation | 5 | 0.95 | 0.77–0.91 | 0.91 (1.09) | MSPSS | 185 | −0.30† | −0.30* |
Physical intimate partner violence | 7 | 0.91 | 0.63–0.85 | 0.28 (0.52) | EPDS | 185 | 0.20† | −0.47† |
Verbal abuse and family conflict | 5 | 0.90 | 0.67–0.86 | 1.29 (0.89) | EPDS | 185 | 0.23† | −0.51† |
Environment-focused | ||||||||
Household economic stress | 6 | 0.83 | 0.42–0.79 | 0.58 (0.68) | SES | 285 | −0.28† | −0.46† |
Community adversity | 5 | 0.75 | 0.41–0.60 | 0.51 (0.67) | SES | 285 | −0.17** | −0.30* |
Full scale | 54 | 7.78 (4.59) | −0.61† | |||||
