topic running a code multiple times on a random sample in SAS Health and Life Sciences

running a code multiple times on a random sample

amin1234 — Fri, 09 Mar 2018 01:32:48 GMT

I am using proc surveyselect to select a random sample of 250 people from the dataset called baseline_followup. I then modify the new random sample to assign everyone a value of 0 for the Ycat variable. I merge the new dataset i named control2 with existing dataset called case. I then go ahead to find the odds ratio of the variables xcat and ycat.

is there a way to run this same code 100 times and find the average odds ratio? because surveyselect will always randomly selected different people. So I want to calculate the 100 different odds ratios and find the average.

Any help is appreciated!

below is the code

proc surveyselect data=baseline_followup
out=control2
method= srs
sampsize=250;
run;

data control2;
modify control2;
Ycat=0;
run;

data casecontrol2;
set case control2;
run;

proc freq data=casecontrol2 order=formatted;
table xcat*ycat/relrisk;
run;

Re: running a code multiple times on a random sample

pau13rown — Fri, 09 Mar 2018 01:49:03 GMT

can you not generate eg 1000 random samples and then use a by statement (by samp) in the proc freq?

Re: running a code multiple times on a random sample

amin1234 — Fri, 09 Mar 2018 04:23:18 GMT

Thank you @pau13rown for your reply. Yes, I can generate 100 random samples. It combines all of them into one dataset. So i can run a proc freq in addition with a by statement to see the frequencies for each replicate. However, I combine the new 100 random samples with another dataset. Replicate values are missing. and so i do not know how to calculate the odds ratio of that. I will appreciate it if you can post a sample code of any method or ideas.

Re: running a code multiple times on a random sample

PGStats — Fri, 09 Mar 2018 04:29:24 GMT

Use OUTHITS in the surveyselect statement to get separate copies of replicates. Or use a weight numberhits; statement in proc freq.

Re: running a code multiple times on a random sample

amin1234 — Thu, 15 Mar 2018 04:42:12 GMT

Thank you all for your responses and ideas! This is how I finally solved it.

--------------------------------------------------------------------------------------

%MACRO domean;
%DO I = 1 %TO 100;
proc surveyselect data=baseline_followup
out=controlmac&i
method= srs
sampsize=250;
run;

data controlmac&i;
modify controlmac&i;
Ycat=0;
run;

data casecohort&i;
set case controlmac&i;
run;

ods trace on;
proc freq data=casecohort&i order=formatted;
table xcat*ycat/relrisk;
run;

ods trace off;

ods output RelativeRisks=Output&i;
proc freq data=casecohort&i order=formatted;
table xcat*ycat/relrisk;
run;

proc print data=Output&i noobs;
run;

%END;
%MEND domean;

%domean

data allrelrisk; set output1-output100;
run;

data onlyodds; set allrelrisk;
where studytype not like 'Co%)';
run;

proc means mean data=onlyodds;
run;