Getting the regression equation for a Poisson regression model

[ammarhm]

Hi everyone,

I have an unusual request from a paper reviewer who wanted to see 'the poisson model equation' generated by our model.

The code I used to construct the model is 

proc glimmix data=have;
class disease sex;
effect yearspline=spline(year / naturalcubic knotmethod=equal(5));
effect agespline=spline(age / naturalcubic knotmethod=equal(5));
model events=disease sex agespline yearspline / dist=poisson offset=logtime s cl link=log; run;

Now I dont really know how to write the regression equation based on the output generated from the code above, the output includes estimates for disease group (4 levels) as well as the year and age spline (5 levels each).

Could anyone please direct and help me?

[SteveDenham]

It is going to be a bit messy because of the two splines, but all of the information you need is provided in the SOLUTION section of the output.  If it isn't apparent how the regression equation, with parameter estimates follows, then post the pertinent section and we should be able to figure it out.

Is there any chance the reviewer was asking for the form of the equation, without the parameter estimates, but as a vector or long-hand equation?

[Rick_SAS · Accepted solution]

I wrote an article that might help you to state how the parameter estimates in the spline model relate to the original variables.