Proper repeat statement for PROC genmod

Question

I think the question is more related to SAS syntax than statistics and is about proper repeated statement for PROC genmod

I am trying to implement Poisson regression with log link and with robust error variance for survey data.

Here is a working code for non survey data that I tested and it works as intended:

proc genmod data = eyestudy;
 class carrot id;
 model lenses = carrot/ dist = poisson link = log;
 repeated subject = id/ type = unstr;
 estimate 'Beta' carrot 1 -1/ exp;
run;

Code above and more information about Poisson regression with log link and with robust error variance but fro non survey data is here: https://stats.idre.ucla.edu/sas/faq/how-can-i-estimate-relative-risk-in-sas-using-proc-genmod-for-common-outcomes-in-cohort-studies/

Below is an example how to use code for PROC genmod for survey analysis (but with dist=binomial link=identity and I think without robust error variance)

proc genmod data=nis10;
class seqnumt estiapt10;
model r_tet_not_utd = / dist=binomial link=identity;
weight provwt;
repeated subject=seqnumt(estiapt10);
where sex = 2;
run;

here strata variable name is estiapt10, cluster variable name is seqnumt and weight variable name is provwt.

Code above and more information about survey data analysis here: https://support.sas.com/resources/papers/proceedings13/272-2013.pdf

My strata variable name is CSTRATM, cluster variable name is CPSUM and weight variable name is PATWT. Dependent variable name is DIETNUTR independent variable name is age_group_var. My data is located in sas_stata. So I tryed this code:

proc genmod data=sas_stata;
class age_group_var id CPSUM CSTRATM;
model DIETNUTR = age_group_var/ dist = poisson link = log;
weight PATWT;
repeated subject = id/ type = unstr;
repeated subject = CPSUM(CSTRATM);
estimate 'Beta' age_group_var 1 -1/ exp;
run;

but it gave me warning:

WARNING: Only the last REPEATED statement is used.

As I understand after reading articles above and some other material I am doing everything right except not the proper repeated statement. For Poisson regression with log link and with robust error variance for survey data I assume there should be some combination of two repeated statements in my code above. I tried several variants of combining those repeated statements but without any luck.

So my question is: What is the code for Poisson regression with log link and with robust error variance for survey data?

SAS2Python SAS2Python · Accepted Answer · 2019-07-15T02:26:24

I am not quite sure I understood what CPSUM(CSTRATM) is. But I am assuming you are looking to use a interactive or nested effect as the subject.

Assuming x = CPSUM(CSTRATM), you could code up the effect as:

repeated subject = id * x

A full survey of coding up effects can be found at

https://support.sas.com/documentation/cdl/en/statug/63347/HTML/default/viewer.htm#statug_genmod_sect038.htm

This might be a useful read also: https://support.sas.com/resources/papers/proceedings/proceedings/sugi29/188-29.pdf

Proper repeat statement for PROC genmod

1 Answers