topic compute age from two dates in SAS Programming

compute age from two dates

archibald — Sun, 19 Jun 2016 18:35:34 GMT

Hi ,

I need to calculate age at graduation. I was wondering if any of the two methods below are appropriate and take care leap years as well.

Method 1: Age= INTCK('year',dob,graduationdate,"C")

Method 2: Age= (graduationdate-dob)/365.25

Thank you very much

Re: compute age from two dates

Reeza — Sun, 19 Jun 2016 18:41:15 GMT

The recommended formula:

age = intck('year',dob,event) - (put(dob,mmddyy4.) > put(event,mmddyy4.)) ;

https://communities.sas.com/t5/SAS-in-Health-Care-Related/Calculating-Age-But-Not-Rounding-Up/td-p/100367

Re: compute age from two dates

PGStats — Sun, 19 Jun 2016 21:40:32 GMT

Isn't it a bit strange that one would have to resort to datestring formatting to calculate an age? The matter depends on a specific case: if you are born on the 29th of February (in a leap year, obviously), do you celebrate your birthday on the 28th of February or on the first of March, during non-leap years? If your answer is the former then your age is

intck("year", dob, event, "continuous") /* birthday on the 28th during non-leap years */

otherwise, your age is

intck('year', dob, event) - (put(dob, mmddyy4.) > put(event, mmddyy4.)) /* birthday on March 1st during non-leap years */

Another option is to use function INT(YRDIF(dob, event, "AGE")). It considers that you will celebrate your birthday on the 28th, even on leap years.

Re: compute age from two dates

archibald — Sun, 19 Jun 2016 22:30:50 GMT

This makes a lot sense.Thanks a lot!

Re: compute age from two dates

archibald — Sun, 19 Jun 2016 22:31:43 GMT

Great! Thank you very much

Re: compute age from two dates

archibald — Sun, 19 Jun 2016 22:34:48 GMT

Great! Thank you very much Reeza