Premorbid functioning as a predictor of outcome in pediatric brain tumor: An initial examination of the normalcy assumption.

Background: Research on neurodevelopmental outcome in survivors of pediatric brain tumor (BT) is often based on the assumption of normal development up to the onset of overt symptoms. We sought to verify the "normalcy assumption" and to investigate corollary issues including challenges inherent to the measurement of premorbid neurobehavioral functioning.

Procedure: The Brain Radiation Investigative Study Consortium (BRISC) is a prospective longitudinal multisite study of 58 children diagnosed with BT.