Creating a Variable using Dates

jcapua2 — Wed, 03 Jan 2018 20:24:09 GMT

Hello,

data have;

patient_num	Procedure_Date	Organ	Multiorgan
patient33	1/24/2000	Heart	No
patient33	5/13/2003	Kidney	Yes
patient33	5/13/2003	Skin	Yes
patient34	5/7/2007	Lung	No
patient34	5/27/2009	Heart	No

data want;

patient_num	Procedure_Date	Organ	Multiorgan	Previous_organ
patient33	1/24/2000	Heart	No	No
patient33	5/13/2003	Kidney	Yes	Yes
patient33	5/13/2003	Skin	Yes	Yes
patient34	5/7/2007	Lung	No	No
patient34	5/27/2009	Heart	No	Yes

I want to create a new variable that flags whether a particular patient has had a previous organ procedure. For example, patient34 has 2 different Procedure_date, with a later Procedure_date that occurred with a different organ, flagging that later row with Previous_organ='Yes' but the prior row (the first Procedure_date) Previous_organ='No.'

Also, for patient33, with 3 Procedure_date, but the last 2 dates occurred on the same date but with different organs. It flags the last 2 dates as Previous_organ='Yes' but the prior row (the first Procedure_date) Previous_organ='No.'

Is there any way to do this in SQL or SAS data step?

Re: Creating a Variable using Dates

Reeza — Wed, 03 Jan 2018 20:26:38 GMT

@jcapua2 wrote:

Hello,

data have;

patient_num Procedure_Date Organ Multiorgan

patient33 1/24/2000 Heart No

patient33 5/13/2003 Kidney Yes

patient33 5/13/2003 Skin Yes

patient34 5/7/2007 Lung No

patient34 5/27/2009 Heart No

data want;

patient_num Procedure_Date Organ Multiorgan Previous_organ

patient33 1/24/2000 Heart No No

patient33 5/13/2003 Kidney Yes Yes

patient33 5/13/2003 Skin Yes Yes

patient34 5/7/2007 Lung No No

patient34 5/27/2009 Heart No Yes

I want to create a new variable that flags whether a particular patient has had a previous organ procedure. For example, patient34 has 2 different Procedure_date, with a later Procedure_date that occurred with a different organ, flagging that later row with Previous_organ='Yes' but the prior row (the first Procedure_date) Previous_organ='No.'

Also, for patient33, with 3 Procedure_date, but the last 2 dates occurred on the same date but with different organs. It flags the last 2 dates as Previous_organ='Yes' but the prior row (the first Procedure_date) Previous_organ='No.'

Is there any way to do this in SQL or SAS data step?

Look up first and last BY GROUP processing. Most of the questions you've asked can be answered using these techniques in a data step.

topic Re: Creating a Variable using Dates in SAS Procedures

Creating a Variable using Dates

Re: Creating a Variable using Dates