Recommendations for management of jaundice in newborns presume thatjaundice is a reliable clinical finding and that the pattern and intensity of jaundice reflects the degree of elevation of the serum bilirubin level. To determine whether experienced observers agree in describing the extent of jaundice and to evaluate the reliability of visual assessment as an indication for the measurement of serum bilirubin levels. Comparison of independent judgments of the extent of jaundice between examiners and with actual serum bilirubin measurements. Well-newborn nursery in an urban public hospital. A convenience sample of 122 healthy term newborns whose bilirubin concentration was measured in the course of standard newborn care. Observers were experienced pediatric nurse practitioners, pediatric house staff, and pediatric attending physicians. Agreement was moderately good for whether an infant's skin was darkly pigmented (K = 0.56). However, agreement between observers regarding the presence of jaundice at each specific body site was poor (0%-23% agreement beyond chance); correlation between estimated bilirubin concentrations was similarly poor (Pearson correlation coefficient, 0.37). Correlation between estimated and actual bilirubin values was slightly better (Pearson correlation coefficient, 0.43-0.54). Clinical examination with visual assessment for jaundice in newborns is neither reliable nor accurate. The decision to perform serum bilirubin testing should be based on additional factors.