Maternal estimates of mental age in developmental assessment

Abstract

To examine the accuracy and clinical utility of maternal estimates of mental age in young children referred for developmental assessment. Mothers of 100 children aged 16 to 60 months referred for developmental evaluation to psychology services of Department of Pediatrics of a tertiary care teaching hospital were asked to estimate the mental age of their child. Maternal estimates were converted to intelligence quotient (IQ) and were compared to results from developmental tests of cognitive and adaptive behavior functioning which were administered to all children. Maternal estimate IQ was highly correlated with IQ calculated from Developmental Profile II (r=.83, p<.001) and social quotient (SQ) calculated from Vineland Social Maturity Scale (r=.81, p<.001). Maternal estimate IQ was 82% sensitive to cognitive delay and 81% specific in identifying children likely to have normal development. Twenty seven percent of the maternal estimates were within +/- 5 IQ points of actual IQ. Mothers were more likely to overestimate their child's functioning. Maternal IQ (Mean=62.1, S.D. =25.8) was significantly higher (t=2.93, p<.004) than the actual IQ (Mean=57.9, S.D.=21.9). Step-wise multiple regression analysis revealed that the child's IQ and SQ explained 10% of the variance (F=6.40, p<.001) in maternal accuracy. The lower the SQ and IQ of the child, more accurate the estimates. Maternal estimates of mental age provide an accurate measure of developmental functioning in young children and may be used as a screening technique to identify a subset of children who need more detailed evaluation.