15 lines
591 B
R
15 lines
591 B
R
# Verify the values found in the Royston paper
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library(survival)
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pbc2 <- na.omit(pbc[,-1]) # no id variable, no missings
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pfit1 <- coxph(Surv(time, status==2) ~ . + log(bili) - bili, pbc2,
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ties="breslow")
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# backwards elimination was used to eliminate all but 8
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pfit2 <- coxph(Surv(time, status==2) ~ age + log(bili) + edema + albumin +
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stage + copper, data=pbc2, ties="breslow")
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temp <- rbind(royston(pfit1), royston(pfit1, adjust=TRUE),
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royston(pfit2), royston(pfit2, adjust=TRUE))
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all.equal(round(temp[,1], 2), c(2.86, 2.56, 2.69, 2.59))
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