topic Proc transpose in SAS Programming

Proc transpose

stancemcgraw — Tue, 18 Jun 2019 16:01:44 GMT

Hi all,

I am trying to calculate the time from the last tube feed (tube_stopped) to the time of surgery. Each patient has multiple tube stop times and also multiple surgeries (date_procedure). I want to create a new variable that calculates this called "Time from last tube feed to procedure" in hours....

Data have:

ID tube_stopped date_procedure

7 12Jul17:02:00:00 13JUL17:13:00:00

7 01AUG17:15:00:00 01AUG17:22:00:00

7 20JUL17:07:35:00 20JUL17:22:00:00

1 29JUL16:01:00:00 29JUL16:23:00:00

1 12AUG16:16:00:00 12AUG16:22:00:00

Data want:

ID tube_stopped date_procedure time from last tube feed to procedure

7 01AUG17:15:00:00 01AUG17:22:00:00 2.4

1 12AUG16:16:00:00 12AUG16:22:00:00 5.7

Re: Proc transpose

Reeza — Tue, 18 Jun 2019 16:19:22 GMT

Use LAG() and basic math, the difference is returned in seconds. To get hours divide by 60 twice.
data want;
set have;
by ID;
Time_Diff = (lag(date_procedure) - tube_stopped)/60/60;
if first.id then call missing(Time_diff);
run;

Re: Proc transpose

Reeza — Tue, 18 Jun 2019 16:20:28 GMT

Actually upon re-reading this, I may have over complicated this, you can just take the difference of each line and don't need the LAG() function.

Re: Proc transpose

stancemcgraw — Tue, 18 Jun 2019 16:31:11 GMT

What does the LAG function do?

Re: Proc transpose

Reeza — Tue, 18 Jun 2019 16:39:42 GMT

LAG gets the previous X row values, I was thinking you need to be looking at the value in the previous row. Lag4 refers to 4 rows back and Lag refers to the previous value