The diagnostic/ prognostic value of neonatal findings for predicting childhood and adult morbidity: systematic reviews, meta-analysis and decision analytic modelling

摘要

Events in utero have been linked with diseases throughout life, however there is a lack of consensus regarding the ability of neonatal tests to predict these outcomes. Systematic reviews and meta-analyses were performed, assessing umbilical cord pH and base excess at birth, standards of low birth weight, and the Apgar score, including a total of 218 papers and 26704980 individuals. The prognostic association and predictive accuracy of these tests for adverse outcomes, including neonatal mortality and morbidity, childhood morbidity including cerebral palsy, and adult outcomes, were determined. A decision-analytic model based analysis assessed the cost-effectiveness of varying the umbilical cord pH threshold, and treatment with neonatal hypothermia. This thesis determined that all of the tests examined had a strong association with neonatal mortality, and a significant but smaller association with neonatal morbidity and childhood cerebral palsy. In general, where the association was strong, tests had a high specificity and positive likelihood ratio for adverse outcome, but poor sensitivity and negative likelihood ratio, indicating that negative tests do not reduce the risk. The cost effectiveness analysis showed that the threshold of pH used in current practice to recommend neonatal hypothermia is more effective and less costly than a higher threshold.