ABSTRACT
Forty two high risk low birth weight infants who had been admitted in neonatal intensive care unit at Yongdong Severance Hospital from August 1987 to July 1990 and followed up in the high risk infants follow-up clinic were studied for evaluation of their development using the Bayley develop-mental test at the age of 9 month(corrected age). The results obtaincd were as follows: 1) Their Mental Developmental Index(MDI)and Psychomotor Developmental Index(PDD)were 99.4+/-12.8 and 101.8+/-16.6 MDI and PDI in birth weight 1000~1500 gm group were 95.3+/-9.8 and 99.3+/-14.3 and the indexes in birth weight 1500~2500gm group were 102.2+/-14.3 and 103.5+/-17.9. 2) There is no statistical significant relationship between the results of Bayley scales and birth weight, cranial ultrasonographic finding, APGAR score, ventilator care and neonatal seizure. However, the MDI was significantly lower in small for gestational age group than appropriate gestational age group. 3) The body weight, height and head circumference measured at the age of 9 month, at the same time when Baylcy developmcntal test was performed, were 45.0+/-29.6, 40.2+/-25.7 and 46.2+/-26.8percentile of Korean Pediatric Growth Standard(1985).