Time-Dependent Hazard Ratio: Modeling and Hypothesis Testing with Application in Lupus Nephritis
时变风险比：建模、假设检验及狼疮性肾炎应用
We investigate the association between duration of untreated disease and survival in lupus nephritis, a rare rheumatologic disease. In this case, as in many other studies of survival, a priori considerations suggest that the effect of the predictor on hazard may change with increasing follow-up time. To accommodate such situations, we use regression splines to model the hazard ratio as a flexible function of time. We propose model-based tests of the hypotheses of hazards…