Universal Scale for Child Development Predicts Limited Intellectual Functioning at an Early Stage

Aim: Early identification of limited intellectual functioning is important for providing support. This study investigated whether a universal child development score (D-score) at 12, 24 and 36 months can predict limited intellectual functioning at 5–10 years of age, in addition to neonatal and parental characteristics.

Methods: A case–control study using developmental milestones and health records from three Dutch child healthcare organisations. D-scores transformed into z-scores (DAZ) were calculated from communication and all milestones.

Results: Data were available for 148 children with an intelligence quotient (IQ) of 50–69, 152 children with an IQ of 70–85 (special education) and 300 controls (mainstream education) at 5–10 years of age. The area under the curve for predicting an IQ of 50–69 was 0.75 using neonatal and parental characteristics. This increased to 0.89 with the addition of DAZ communication scores and to 0.94 with the inclusion of DAZ scores using all milestones instead of only communication milestones. For predicting an IQ of 70–85, these values were 0.67, 0.75 and 0.79, respectively.

Conclusion: In addition to neonatal and parental characteristics, early child development significantly predicted limited intellectual functioning. The D-score, currently derivable from 14 different instruments, serves as a powerful predictive tool in clinical practice.