R Under development (unstable) (2024-12-13 r87441 ucrt) -- "Unsuffered Consequences"
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> # Verify the values found in the Royston paper
> library(survival)
> 
> pbc2 <- na.omit(pbc[,-1])  # no id variable, no missings
> 
> pfit1 <- coxph(Surv(time, status==2) ~ . + log(bili) - bili, pbc2,
+                ties="breslow")
> # backwards elimination was used to eliminate all but 8
> pfit2 <- coxph(Surv(time, status==2) ~ age + log(bili) + edema + albumin +
+                    stage + copper, data=pbc2, ties="breslow")
> 
> temp <- rbind(royston(pfit1), royston(pfit1, adjust=TRUE),
+               royston(pfit2), royston(pfit2, adjust=TRUE))
> all.equal(round(temp[,1], 2), c(2.86, 2.56, 2.69, 2.59))
[1] TRUE
> 
> proc.time()
   user  system elapsed 
   0.76    0.17    0.87