Determine if value is consistent by subject

[mglogan]

Hello,

I need to determine if the lab collection method for each subject in my data set was collected consistently throughout the study.

To Illustrate, the variables I will use are "Lab Location" and "Subject ID." Each subject has multiple observations in the data set.

I need to determine if the value of "Lab Location" (Character) is the same for all observations per Subject ID. if not, I need to output to view the result. 

Example Data:

SubjectID  LabLocation Visit

Subj123     Lab                     1
Subj123     Lab                     2
Subj123     Point of Care      3

Can you recommend the best method for doing this?

Thank you!

[Reeza · Accepted solution]

proc sql;
create table not_same as
select *
from have
group by subjectID
having not (max(labLocation)=Min(labLocation));
quit;

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@mglogan wrote:

Hello,

I need to determine if the lab collection method for each subject in my data set was collected consistently throughout the study.

To Illustrate, the variables I will use are "Lab Location" and "Subject ID." Each subject has multiple observations in the data set.

I need to determine if the value of "Lab Location" (Character) is the same for all observations per Subject ID. if not, I need to output to view the result. 

Example Data:

SubjectID  LabLocation Visit

Subj123     Lab                     1
Subj123     Lab                     2
Subj123     Point of Care      3

Can you recommend the best method for doing this?

Thank you!

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