topic sas code help in SAS Programming

sas code help

rashmirao99 — Wed, 26 Feb 2020 22:15:26 GMT

Hi ,

I need to create baseline values: The dataset I have as follows:

subjid paramcd visit aval

001 dbp 1 72

001 dbp 2 60

001 dbp 3 78

001 dbp 4 80

The desired dataset:

subjid paramcd visit aval base

001 dbp 1 72 72

001 dbp 2 60 72

001 dbp 3 78 72

001 dbp 4 80 72

if aval=72 is the baseline.

Thanks.

Re: sas code help

novinosrin — Wed, 26 Feb 2020 22:31:48 GMT

data have;
input subjid  $       paramcd   $  visit           aval;
cards;
001              dbp            1               72
001              dbp           2                 60
001              dbp           3                 78
001              dbp          4                   80
;

data want;
 set have;
 by subjid;
 retain base;
 if first.subjid then base =aval;
run;

Hi @rashmirao99 The idea is

1. You need to assign the first observation of a by group i.e each subjid to a new variable called base

2. Retain the value of base once assigned across iterations within each subjid by group, otherwise the value of base is reinitialized to missing for each iteration of the datastep.

Re: sas code help

rashmirao99 — Thu, 27 Feb 2020 17:08:26 GMT

No. That doesn't work. It only populates for the first record.

What I want is suppose I have something like this:

001              dbp            1               72
001              dbp           2                 60
001              dbp           3                 78
001              dbp          4                   80

001 hr 1 45

001 hr 2 55

001 hr 3 60

and The output data I'm expecting is this:

subjid test visit aval base

001              dbp            1               72          72
001              dbp           2                 60         72
001              dbp           3                 78         72
001              dbp          4                   80        72

001 hr 1 45 45

001 hr 2 55 45

001 hr 3 60 45.

Thanks.

Re: sas code help

novinosrin — Thu, 27 Feb 2020 17:21:25 GMT

Hi @rashmirao99 Here is a test-->


data have;
input subjid  $       paramcd   $  visit           aval;
cards;
001              dbp            1               72
001              dbp           2                 60
001              dbp           3                 78
001              dbp          4                   80
001              hr             1                   45
001              hr             2                   55
001              hr             3                   60
;

data want;
 set have;
 by subjid paramcd;
 retain base;
 if first.paramcd then base =aval;
run;

subjid	paramcd	visit	aval	base
001	dbp	1	72	72
001	dbp	2	60	72
001	dbp	3	78	72
001	dbp	4	80	72
001	hr	1	45	45
001	hr	2	55	45
001	hr	3	60	45

subjid	paramcd	visit	aval	base
001	dbp	1	72	72
001	dbp	2	60	72
001	dbp	3	78	72
001	dbp	4	80	72
001	hr	1	45	45
001	hr	2	55	45
001	hr	3	60	45

subjid	paramcd	visit	aval	base
001	dbp	1	72	72
001	dbp	2	60	72
001	dbp	3	78	72
001	dbp	4	80	72
001	hr	1	45	45
001	hr	2	55	45
001	hr	3	60	45

subjid	paramcd	visit	aval	base
001	dbp	1	72	72
001	dbp	2	60	72
001	dbp	3	78	72
001	dbp	4	80	72
001	hr	1	45	45
001	hr	2	55	45
001	hr	3	60	45