topic Re: Proc summary, Weight in SAS Programming

Proc summary, Weight

Ivy — Thu, 04 Nov 2021 01:57:02 GMT

Hello,

I am applying weight statement at proc summary below.

However, it did not bring the weighted count.

I am wondering how this can work. Thanks.

(Just use proc summary , no proc freq).

proc summary data=a1 chartype completetypes;
class treatment;
types treatment;
weight IPW; /*weight dose not work?*/
output out=ae_1;
quit;

Re: Proc summary, Weight

ballardw — Thu, 04 Nov 2021 03:27:27 GMT

If your IPW variable is a count then you likely mean to use FREQ not Weight statement.

proc summary data=a1 chartype completetypes;
class treatment;
types treatment;
Freq IPW; 
output out=ae_1;
quit;

Freq uses the variable as a count of records where all the variables are the same.(or at least the one you are using for other statements in the procedure).

Weight will not change the sample size the way Freq does.

Re: Proc summary, Weight

PaigeMiller — Thu, 04 Nov 2021 11:23:01 GMT

However, it did not bring the weighted count.

You can compute the sumwgt statistic.

proc summary data=a1 chartype;
class treatment;
weight IPW; 
output out=ae_1 sumwgt=sum_weights /* Other statistics required go here */;
quit;

Re: Proc summary, Weight

Ivy — Thu, 04 Nov 2021 13:05:35 GMT

Thanks Paige for the suggestion.
I customized your code , "adding var statement" as below, then it works!
proc summary data=a1 chartype completetypes;
class treatment;
types treatment;
var ipw;
weight IPW;
output out=ae_1 sumwgt=sum_weights;
quit;

Re: Proc summary, Weight

Ivy — Thu, 04 Nov 2021 13:10:40 GMT

Thanks for the response.
Yes. Proc Freq is the normal way for the count.
I am using PROC SUMMARY, due to try not to change the reference program I got from others , but I need to add weight for the patients.

Re: Proc summary, Weight

Ivy — Thu, 04 Nov 2021 13:13:23 GMT

The following is much clear to understand the weighted count by proc summary.

proc summary data=a1 chartype completetypes;
class treatment;
types treatment;
var ipw;
output out=ae_1 sum=sum_weights;
quit;