In Reply.—Dr Goodlin is puzzled about the differing outcomes of the various analyses of the CPS data. Our placing the various disorders that cause birth asphyxia into a single category and grouping other risk factors into consolidated categories made it possible to identify the origin of a much higher percentage of CP cases than was possible in previous studies of the CPS data. Previous analyses isolated the origin of very few CP cases in explanatory models because the CPS had too few children in single category classifications to identify associations between most individual risk factors and CP. Most previous CPS investigators also used Apgar scores to identify asphyxiated neonates. Our study found that this use of Apgar scores misattributes to asphyxia many cases of CP that have a developmental origin.
Dr Goodlin suggested that some infants who died in the CPS as the result of birth asphyxia would have survived with