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Complex Samples Cox Regression
There are multiple cases for some subjects, and all 3,310 cases are used in the analysis.
The design has a single stratum and 2,421 units (one for each subject). The sampling design degrees of freedom are estimated by 2421−1=2420.
Tests of Model Effects
Figure
Tests of model effects
The significance value for each effect is near 0, suggesting that they all contribute to the model.
Parameter Estimates
Figure
Parameter estimates
The procedure uses the last category of each factor as the reference category; the effect of other categories is relative to the reference category. Note that while the estimate is useful for statistical testing, the exponentiated estimate, Exp(B), is more easily interpreted as the predicted change in the hazard relative to the reference category.
The value of Exp(B) for [mi=0] means that the hazard of death for a patient with no prior myocardial infarctions (mi) is 0.002 times that of a patient with three prior mi’s.