A threshold-free summary index of prediction accuracy for censored time to event data.
Prediction performance of a risk scoring system needs to be carefully assessed before its adoption in clinical practice. Clinical preventive care often uses risk scores to screen asymptomatic population. The primary clinical interest is to predict the risk of having an event by a prespecified future time t0 . Accuracy measures such as positive predictive values have been recommended for evaluating the predictive performance. However, for commonly used continuous or ordinal risk score systems, these measures require a subjective cutoff threshold value that dichotomizes the risk scores. The need for a cutoff value created barriers for practitioners and researchers. In this paper, we propose a threshold-free summary index of positive predictive values that accommodates time-dependent event status and competing risks. We develop a nonparametric estimator and provide an inference procedure for comparing this summary measure between 2 risk scores for censored time to event data. We conduct a simulation study to examine the finite-sample performance of the proposed estimation and inference procedures. Lastly, we illustrate the use of this measure on a real data example, comparing 2 risk score systems for predicting heart failure in childhood cancer survivors.
['Yuan|Yan|Y|0000-0002-2073-9924', 'Zhou|Qian M|QM|', 'Li|Bingying|B|', 'Cai|Hengrui|H|', 'Chow|Eric J|EJ|', 'Armstrong|Gregory T|GT|']
D001699:Biometry D000073116:Cancer Survivors D003198:Computer Simulation D006333:Heart Failure D006801:Humans D011237:Predictive Value of Tests D018570:Risk Assessment D012307:Risk Factors D018709:Statistics, Nonparametric D013997:Time Factors
screening positive predictive value censored event time precision-recall curve risk prediction time-dependent prediction accuracy