Comparison of chronological and corrected ages in the gross motor assessment of low-risk preterm infants during the first year of life.

OBJECTIVE To evaluate the need of chronological age correction according to the degree of prematurity, when assessing gross motor development in preterm infants, during the first year of life. METHOD Cohort, observational and prospective study. Alberta Infant Motor Scale (AIMS) was used to evaluate 43 preterm infants with low risk for motor neurological sequelae, during the first year of corrected age. Mean scores were analyzed according to chronological and corrected ages. Children with motor neurological sequelae were excluded during follow-up. RESULTS Gross motor mean scores in preterm infants tended to be higher when corrected age was used compared with those obtained when using chronological age, during the first twelve months. At thirteen months of corrected age, an overlapping of confidence intervals between corrected and chronological ages was observed, suggesting that from that period onwards correction for the degree of prematurity is no longer necessary. CONCLUSION Corrected age should be used for gross motor assessment in preterm infants during the first year of life.