Reclassification is observed even when there is no or minimal improvement in the area under the receiver operating characteristic curve (AUC), and it is unclear whether it indicates improved clinical utility. The authors investigated total reclassification, net reclassification improvement, and integrated discrimination improvement for different DeltaAUC using empirical and simulated data. Empi...

results the command is addpred for logistic regression models. conclusions the stata package provided herein can encourage the use of novel methods in examining predictive capacity of ever-emerging plethora of novel biomarkers. materials and methods we have written a stata command that is intended to help researchers obtain cut point-free and cut point-based net reclassification improvement ind...

conclusions herein we have described the stata package “adpredsurv” for calculation of the nam-d’agostino x2 goodness of fit test as well as cut point-free and cut point-based nri, relative and absolute idi, and survival-based regression analyses. we hope this work encourages the use of novel methods in examining predictive capacity of the emerging plethora of novel biomarkers. background a fun...

results age was selected as the important factor based on all 7 statistics. exclusion of age variable decreased c index from 0.75 to 0.68 and r square from 0.25 to 0.15. duration of hospitalization was important based on 4 statistics. exclusion of this variable decreased r square from 0.25 to 0.21. while gender was a useful variable in separation of patients into risk groups, its omission did n...

Risk reclassification methods have become popular in the medical literature as a means of comparing risk prediction models. In this issue of the Journal, Pencina et al. (Am J Epidemiol. 2012;176(6):492-494) present further results for continuous measures of model discrimination and describe their characteristics in nested models with normally distributed variables. Measures include the change i...

BACKGROUND The incremental prognostic value of myocardial perfusion-gated single photon emission computed tomography (MPGS) compared with exercise test has not yet been properly evaluated. METHODS AND RESULTS Five thousand six hundred seventy-two consecutive patients with known or suspected coronary disease undergoing exercise MPGS between 1997 and 2007 were included. Three-year predictive mo...

The Gender-Age-Physiology (GAP) model is a validated, baseline-risk prediction model for mortality in idiopathic pulmonary fibrosis. Longitudinal variables have been shown to contribute to risk prediction in idiopathic pulmonary fibrosis and may improve the predictive performance of the baseline GAP model. Our aims were to further validate the GAP model and evaluate whether the addition of long...

Net reclassification indices have recently become popular statistics for measuring the prediction increment of new biomarkers. We review the various types of net reclassification indices and their correct interpretations. We evaluate the advantages and disadvantages of quantifying the prediction increment with these indices. For predefined risk categories, we relate net reclassification indices...