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Abstract

We appreciate Dr Ahlfors’ continuing interest in our work and his comments on the statistical method. Dr Ahlfors suggests that our “fatal flaw” is the use of correlation, which he says, “... cannot be applied to mathematically related variables.” Correlation can be applied in such a relationship but would be of no value, because all the data points would follow the graph of the mathematical relationship. The data shown in our scatter plot indicate clearly this is not the case, so the use of correlation is valuable. Among the contributing factors to the variability is the fact that “n,” the binding function of albumin for MADDS, is not constant in neonatal serum. We presume this variability is because varying amounts of the albumin are nonbinding.1Ebbesen F Brodersen R Risk of bilirubin acid precipitation in preterm infants with respiratory distress syndrome: considerations of blood/brain bilirubin transfer equilibrium.Early Hum Dev. 1982; 6: 341-355Abstract Full Text PDF PubMed Scopus (23) Google Scholar, 2Ebbesen F Foged N Brodersen R Reduced albumin binding of MADDS: a measure for bilirubin binding in sick children.Acta Pediatr Scand. 1986; 75: 550-554Crossref PubMed Scopus (7) Google Scholar In the patients we studied, the bilirubin/albumin ratio was not helpful in predicting the reserve albumin binding capacity. In healthy term infants, in whom there may be less variability of “n,” the bilirubin/albumin ratio may be more useful. What is still needed in caring for jaundiced infants is a simple method of measuring residual bilirubin-binding ability.