topic Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot in Advanced Programming

Variable to identify individuals whose type of diabetes changes from one hospital visit to another

Wylyann — Thu, 24 Mar 2022 19:19:17 GMT

Hello, can anyone help me?
I have some medico-administrative data and I want to create a binomial variable that will code an individual as 1, if the type of diabetes diagnosed is constant from one hospital visit to another; and code 0, if the type of diabetes diagnosed varies according to the hospital visit.
This is what my medico-administrative data looks like:

Observation (numeric)	Id (numeric)	Hospital visit Number (alphanumeric)	Type of diabetes diagnosed (numeric)
1	3	04	2
2	3	05	2
3	3	07	2
4	15	01	1
5	15	02	2
6	18	03	1
7	22	06	2
8	30	01	2
9	30	03	1
10	30	04	1

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

PeterClemmensen — Thu, 24 Mar 2022 19:31:21 GMT

Across all distinct hospital visits?

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

ballardw — Thu, 24 Mar 2022 19:33:47 GMT

Can you show what you expect the result to look like?

Are the ONLY values for the diabetes variable 1 and 2?

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

Wylyann — Thu, 24 Mar 2022 19:39:41 GMT

No, for each individual.

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

Wylyann — Thu, 24 Mar 2022 20:03:44 GMT

Yes, the only values for the diabetes variable are 1 (type 1 diabetes mellitus) and 2 (type 2 diabetes mellitus).

This involves writing a command that automatically creates the variable "Type of diabetes evolution" (TDevolution) that assigns code 1 to individuals (Id) "3", "18" and "22"; then code 0 to Id "15" and "30".

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

Wylyann — Thu, 24 Mar 2022 20:09:20 GMT

My data contains more than 20,000 observations. What I present here is only a Sample.

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

mkeintz — Fri, 21 Mar 2025 03:27:27 GMT

Read each ID twice, the first time to set a flag if there is a change in diabetes type. The second time to output data if the flag was set:

But the original code I sent included the NOTSORTED option in the by statement - which is not supported when SET has more than one input dataset. So "by id diabetes_type nosorted" needs to be reset to "by id", and the subsequent code needs to be changed, as here:

data want (drop=_:);
  set have (in=firstpass)  have (in=secondpass);
  by id;
  retain _keep_this_id 0;
  if first.id=1 then _keep_this_id=0;
  if first.id=0 and diabetes_type^=lag(diabetes_type) then _keep_this_id=1;
  if secondpass=1 and _keep_this_id=1;
run;

The original code (below) should not be used, and will be flagged by SAS:

data want (drop=_:);
  set have (in=firstpass)  have (in=secondpass);
  by id diabetes_type notsorted;
  retain _keep_this_id 0;
  if first.id=1 then _keep_this_id=0;
  if first.id=0 and first.diabetes_type=1 then _keep_this_id=1;
  if secondpass=1 and _keep_this_id=1;
run;

The first.id=0 and first.diabetes=1 condition tests for a change in diabetes others than at the beginning of the ID. Because diabetes can change up, or change down., the BY statement has the notsorted parameter.

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

ballardw — Thu, 24 Mar 2022 22:18:06 GMT

@Wylyann wrote:
Yes, the only values for the diabetes variable are 1 (type 1 diabetes mellitus) and 2 (type 2 diabetes mellitus).

This involves writing a command that automatically creates the variable "Type of diabetes evolution" (TDevolution) that assigns code 1 to individuals (Id) "3", "18" and "22"; then code 0 to Id "15" and "30".

Still have NOT shown what the resulting data set is supposed to look like.

Re: Variable to identify individuals whose type of diabetes changes from one hospital visit to anot

Wylyann — Mon, 28 Mar 2022 15:43:44 GMT

Maybe I didn't understand you correctly. Can you reformulate your question, please?