We describe the application of a revised version of the Dubowitz neurologic examination of the newborn in 224 low-risk, term newborn infants. The method has been updated by eliminating less useful items and including new items evaluating general movements and patterns of distribution of tone. An optimality score is included to make the evaluation more quantitative and for comparison with sequential examinations with neurophysiologic and imaging findings. The score is based on the distribution of the scores for each item in the population of low-risk term infants. We defined not only the most common pattern for each item but also the variability of the findings by using 10th and 5th centiles. Because most of the items assessing tone and the Moro reflex varied with gestational age between 37 and 42 weeks, the changes were incorporated in the scoring system. The total optimality score was the sum of the optimality scores of individual items. Although the association of 4 or more deviant scores was found in less than 10% of our infants, deviant results on 1 or 2 single items could be observed in a third of this normal population, suggesting that isolated deviant signs have little diagnostic value. In contrast, an abnormal distribution of tone patterns, which we have commonly observed in infants with brain lesions, was not found in this cohort. (J Pediatr 1998;133:406-16)