Clinical parameters, available on day 4, were collected for 204 ventilated neonates < 32 weeks gestation. Logistic regression was used to identify factors significantly and independently associated with chronic neonatal lung disease (CNLD) at 36 weeks postconception, which developed in 29% of neonates. At 36 weeks birth weight, peak inspiratory ventilator pressure and requirement for assisted ventilation on day 4 were such factors. The logistic regression equation for this association was applied to each infant resulting in a value between 0 and 1. By knowing which neonates developed CNLD, the discriminatory ability in this value was assessed. A receiver-operator characteristic curve for this value had an area under the curve of 0.97 (SE 0.03) in a unrelated population. A logistic equation value > 0.4 had a sensitivity of 90% and a specificity of 88% in predicting CNLD at 36 weeks.
Conclusion: Use of logistic regression to identify factors independently associated with chronic drug disease at 36 weeks postconception, allowed accurate prediction of this disorder. This would allow reduction in size of randomised trials of early intervention in chronic lung disease.