To perform an in depth evaluation of children, and thus provide a systematic method of managing children, who after infantile health screening, were categorized as suspected developmental delay.

78 children referred to the Developmental Delay Clinic of Ilsan Hospital after suspected development delay on infantile health examinations were enrolled. A team comprised of a physiatrist, pediatrician and pediatric psychiatrist examined the patients. Neurological examination, speech and cognitive evaluation were done. Hearing tests and chromosome studies were performed when needed clinically. All referred children completed K-ASQ questionnaires. Final diagnoses were categorized into specific language impairment (SLI), global developmental delay (GDD), intellectual disability (ID), cerebral palsy (CP), motor developmental delay (MD) or autism spectrum disorder (ASD).

72 of the 78 patients were abnormal in the final diagnosis, with a positive predictive value of 92.3%. Thirty (38.4%) of the 78 subjects were diagnosed as GDD, 28 (35.8%) as SLI, 5 (6.4%) as ASD, 9 (12.5%) as MD, and 6 (7.6%) as normal. Forty five of the 78 patients had risk factors related to development, and 18 had a positive family history for developmental delay and/or autistic disorders. The mean number of abnormal domains on the K-ASQ questionnaires were 3.6 for ASD, 2.7 for GDD, 1.8 for SLI and 0.6 for MD. Differences between these numbers were statistically significant (p<0.05).

Because of the high predictive value of the K-ASQ, a detailed evaluation is necessary for children suspected of developmental delay in an infantile health promotion system.