Severity and characteristics of developmental delay can be assessed using variability measures of sitting posture.

PURPOSE: We sought to identify measures of variability from sitting postural sway that are significantly different among infants who were developing typically, those who were developmentally delayed or hypotonic, and those who later on had a diagnosis of spastic or athetoid cerebral palsy.
METHODS: Sixty-five infants were evaluated when they were just developing the ability to sit upright by assessing center of pressure (COP) data, using measures of both amount and temporal organization of COP variability.
RESULTS: The results indicated that measures of variability of COP could discriminate between infants with developmental delay and infants with cerebral palsy and add to the description of sitting postural behavior.
CONCLUSIONS: Our method of evaluating sitting postural control could be an objective tool to help describe distinctive features of motor delay in an individual infant and could lead in the design of selective therapeutic interventions for improving postural control of infants with motor delays.