How to calculate Log Hazard Ratio in SAS

proc phreg data = analysis ;
class c diabetes /descending;
model days*ind(0) = c diabetes id/ rl ;
id= c *diabetes;
hazardratio id;
I am trying to run a simple Cox Regression in SAS. I cant seem to find a way to calculate log-hazard ratio for my variables in the model. The hazard ratio statement and the /rl options gives hazard ratio with 95% CI, but I want log-hazard ratio with 95% CI limits.

Please help.


Not a robit
I will check this out in the morning when i have access to a computer. Since you have covariates this wouldnt be "simple ". What is the "id" variable, it appears to be continuous?


Not a robit

That is, β is the logarithm of the ratio of the hazard rate for subjects

belonging to the group denoted by
X = 1 to the hazard function for subjects

belonging to the group indicated by

X = 0.

The parameter β is a log relative risk and exp(β) is a relative risk of

response; PH regression is sometimes called “relative risk regression”.

• If we conclude that the data provide reasonable evidence to contradict the

hypothesis that

X is unrelated to response, exp( ˆ β) is a point estimate of the

rate at which response occurs in the group denoted by

X = 1 relative to the

rate at which response occurs at the same time in the group denoted by

X = 0.

A confidence interval for β, given by ˆ β ・} 1.96SE, represents a range of

plausible values for the log relative risk associated with the corresponding

explanatory variable.

See sas paper from global forum : #253-2010, for coding options.
Thanks for your help with this. I am familiar with this paper and it does provide a very good overview of using some of the more complicated options in CLASS, CONTRAST, and HAZARDRATIO Statements.

I simply used the CONTRAST statement to calculate the log-hazard ratio with the 95% CI. There is no other easy way to do this in SAS. So one has to write out the contrast statement for every permutation and combination - and it does get complicated if you have interactions in your model.

Thanks again!


Not a robit

Can you post your code, so to help others with this same question. You can change variable names to deidentify you research/project. And yes, the 253-2010 paper seemed very helpful in regards to some available options.
Here's the code for the solution. Nothing too complicated but you need to know how to correctly write the contrast statement:

proc phreg data = analysis ;
	class 			cat1 (ref="yes") cat2 (ref="yes") /descending;
	model 		days*ind(0) = cat1 | cat2/ rl;
hazardratio cat1 /diff=ref ;
contrast 'test this value, should be same as that from hazratio statement' cat1 1 / estimate = both;
contrast 'cat1=yes for cat2=yes' cat1 1 cat1*cat2 1 / estimate = both;