BookmarkSubscribeRSS Feed
TEJ
Calcite | Level 5 TEJ
Calcite | Level 5

Hi,

I am working on a lab data with different test types and corresponding specimen dates. I have included a snapshot of my data in the attachment (only tests included, there's dates for each test like date1, date2, date3 etc. for test1, test2, test3 resp).

 

there are 4 kinds of tests-

EIA IgM, EIA total, WB IgM and WB IgG.

I want to obtain proportion/counts of of observations who had -

1) WB IgG- 

2) EIA (total or IgM) followed by WB IgM within 30 days

3)both combinations (1 AND 2)

4)neither (like those with only EIAs, or EIA followed by WBIgG but not within 30 days).

 

PLEASE SUGGEST!

 

 

 

5 REPLIES 5
PGStats
Opal | Level 21

Please post test data in machine readable form.

PG
RW9
Diamond | Level 26 RW9
Diamond | Level 26

For a good response, post some test data, in the form of a datastep (most wont download files or type test data in for you), and an example of what the output should look like.  You should be able to do this in multiple ways (proc freq/means/summary, or datastep retain count on sorted dataset, or proc sql).

TEJ
Calcite | Level 5 TEJ
Calcite | Level 5

CaseID

TEST1

TEST2

TEST3

TEST4

DATE1

DATE2

DATE3

DATE4

1

WB IgG

 

 

 

2/5/2015

 

 

 

2

WB IgG

EIA total

EIA total

 

3/4/2015

3/4/2015

7/13/2015

 

3

EIA IgM

WB IgM

WB IgG

 

3/4/2016

3/4/2016

7/3/2016

 

4

EIA total

WB IgG

WB IgG

WB IgG

2/4/2015

2/4/2015

7/7/2015

12/2/2015

5

WB IgM

EIA total

 

 

7/11/2015

9/11/2015

 

 

6

WB IgM

WB IgG

EIA total

 

12/12/2015

12/12/2015

3/12/2016

 

7

WB IgM

WB IgG

EIA total

WB IgM

10/8/2015

10/8/2015

11/2/2015

11/2/2015

 

 

And re:output- as outlined in my first post, I am looking at different combinations of tests (used to “confirm” a case’s disease status) for each observations.

If WB IgG (regardless of other tests performed on that ID) say cat=1

If EIA total/EIA IgM and is followed by WB IgM within 30 days, cat=2

If cat=1 is true AND cat=2 is true, cat=3

If neither (only EIA total, EIA IgM, WB IgM but not within 30 days), cat=4.

Output I want will be a basic proc freq of “cat”.

 

hope this helps understand what i need

 

Thanks a lot!

ballardw
Super User

Is the case of WB IgM preceding EIA total or EIA IgM to be considered category 4?

 

This is a poorly worded description of assigning a single category variable as the first line contradicts the second when the

"regardless of other tests" is used in the definition.

   If WB IgG (regardless of other tests performed on that ID) say cat=1

 

   If cat=1 is true AND cat=2 is true, cat=3

 

You need to clarify which combinations of other tests will yield a cat=1

 

For this one:

   If EIA total/EIA IgM and is followed by WB IgM within 30 days, cat=2

What happens if you have both EIA total and EIA IgM but the WB lgm is within 30 days of only one of them?

PGStats
Opal | Level 21

Converting your data to a long structure help a lot:

 

data have;
infile datalines dsd;
input CaseID	(TEST1	TEST2	TEST3	TEST4) (:$8.)	(DATE1	DATE2	DATE3	DATE4)(:mmddyy.);
datalines;
1,WB IgG, , , ,2/5/2015, , , 
2,WB IgG,EIA total,EIA total, ,3/4/2015,3/4/2015,7/13/2015, 
3,EIA IgM,WB IgM,WB IgG, ,3/4/2016,3/4/2016,7/3/2016, 
4,EIA total,WB IgG,WB IgG,WB IgG,2/4/2015,2/4/2015,7/7/2015,12/2/2015
5,WB IgM,EIA total, , ,7/11/2015,9/11/2015, , 
6,WB IgM,WB IgG,EIA total, ,12/12/2015,12/12/2015,3/12/2016, 
7,WB IgM,WB IgG,EIA total,WB IgM,10/8/2015,10/8/2015,11/2/2015,11/2/2015
;

data long;
set have;
array t test:;
array d date:;
do i = 1 to dim(t);
    if not missing(t{i}) then do;
        test = t{i}; date = d{i}; output;
        end;
    end;
keep caseId test date;
run;

proc sql;

create table cat1 as
select unique caseId 
from long where test="WB IgG";

create table cat2 as
select unique a.caseId 
from long as a inner join long as b 
on a.caseId=b.caseId and intck("DAY", a.date, b.date) <= 30
where a.test in ("EIA total", "EIA IgM") and b.test = "WB IgM";

create table cat3 as
select * from cat1
intersect
select * from cat2;

create table cat4 as
select unique caseId from long
except
select * from cat1
except
select * from cat2;

create table cat as
select unique 
    caseId,
    caseId in (select * from cat1) as cat1,
    caseId in (select * from cat2) as cat2,
    caseId in (select * from cat3) as cat3,
    caseId in (select * from cat4) as cat4
from long
order by caseId;

select * from cat;

quit;
PG

SAS Innovate 2025: Register Now

Registration is now open for SAS Innovate 2025 , our biggest and most exciting global event of the year! Join us in Orlando, FL, May 6-9.
Sign up by Dec. 31 to get the 2024 rate of just $495.
Register now!

What is Bayesian Analysis?

Learn the difference between classical and Bayesian statistical approaches and see a few PROC examples to perform Bayesian analysis in this video.

Find more tutorials on the SAS Users YouTube channel.

SAS Training: Just a Click Away

 Ready to level-up your skills? Choose your own adventure.

Browse our catalog!

Discussion stats
  • 5 replies
  • 1612 views
  • 0 likes
  • 4 in conversation