The study aimed to assess how well the severity of clinical conditions in extremely low birth weight infants in the first 12 h of life, as measured by the CRIB (clinical risk index for babies), relates to hospital outcome and subsequent disability at 18 months of age. The CRIB was confirmed as a valid index of initial neonatal risk, even in extremely low birth weight infants, predicting hospital outcome (death or major brain lesions) more accurately than birth weight or gestational age. However, an adjustment of the CRIB score for gestational age might enhance its positive predictive value in relation to short-term developmental outcome in this particular population.