Restructuring a dataset

SAS_user122 — Wed, 11 May 2022 16:57:13 GMT

Hi! I have a dataset that looks like this:

patient_id start_date end_date

123 01Jan2016 15Apr2020

321 09Sep2018 17Nov2019

567 07Jul2017 09Jul2020

567 09Sep2020 10Dec2020

My study period is 01Jan2016-31Dec2020. I want to create a new variable called time that creates a flag if someone's study period included that particular month (ex. 1=Jan2016, 2=Feb2016, etc). So my data set would end up looking like this:

patient_id start_date end_date time

123 01Jan2016 15Apr2020 1

123 01Jan2016 15Apr2020 2

123 01Jan2016 15Apr2020 3

123 01Jan2016 15Apr2020 4

etc

Any thoughts on how to do this?

Re: Restructuring a dataset

PaigeMiller — Wed, 11 May 2022 17:00:16 GMT

So what is the expected output for patient_id 321 and patient_id 567?

Is the first month always January 2016, or does it vary by patient_id?

What is the last month to use?

topic Restructuring a dataset in SAS Programming

Restructuring a dataset

Re: Restructuring a dataset