A parent‐completed developmental questionnaire: Follow up of ex‐premature infants

Objective : Premature infants are at increased risk of developmental disability. Early identification of problems allows intervention to ameliorate or attenuate problems. A reliable screening tool allows triage of children in this high‐risk population by identifying those unlikely to need full developmental assessment. To explore the test characteristics of an established parent‐completed developmental assessment questionnaire ‘Ages and Stages Questionnaire’ (ASQ) in follow up of an Australian population of premature infants. Methodology : One hundred and sixty‐seven children born prematurely with corrected ages 12‐ to 48‐months attending the Growth and Development Clinic at the Mater Children’s Hospital in Brisbane, Queensland, Australia; 136 questionnaires ‘ASQ’ were returned completed (81%) and were compared to formal psychometric assessment (Griffith Mental Development Scales for 12‐ and 24‐months, Bayley Mental Development Intelligence Scale for 18‐months, McCarthy General Cognitive Intelligence Scale for 48‐months). Developmental delay was considered to be present if any of the above psychometric assessments fell below 1.0 standard deviations (SD). The ASQ cut‐off used was 2.0 SD (US data derived means and SD). Results : Aggregate results for all age groups comparing ASQ to psychometric assessments as ‘gold standards’ found the ASQ to have the following test characteristics: sensitivity (90%); specificity (77%); positive predictive value (40%); negative predictive value (98%); % over‐referred (20%); % under‐referred (1%); % agreement (79%). Likelihood ratio for children failing the ASQ was 3.8 and for passing the ASQ was 0.13. Twenty‐one children with known disabilities were included in the study and in 14 of these, the ASQ overall score agreed with the psychometric assessment (67%). Conclusion : The high negative predictive value of the ASQ supports its use as a screening tool for cognitive and motor delays in the follow up of ex‐premature infants. This would need to be combined with other strategies as part of a comprehensive follow up program for ex‐premature infants.