topic Re: How to calculate Area Under the Curve for longitudinal data organized in columns (SPLIT)? in Discussions

How to calculate Area Under the Curve for longitudinal data organized in columns (SPLIT)?

sornasst — Tue, 19 Sep 2017 16:51:17 GMT

Dear JMP community,

I would like to derive the Area Under the Curve for the change in a varible through time. The data is organized in columns (time points) with patients in rows (see below)

Pat_ID	Time 0w	Time 2w	Time 4w	Time 8w
AAA	0	-0.3	-1.2	-1.5
BBB	0	0.1	-0.3	0.2
CCC	0	-1.5	-2.3	-2.8
DDD	0	-0.6	-0.4	-0.5

I could not find a preexisting function that would allow to do that so is there an elegant wasy to do this or should I bite the bullet and sum the areas of each parallelograms?

Thank you for your help.

Thierry

Re: How to calculate Area Under the Curve for longitudinal data organized in columns (SPLIT)?

ian_jmp — Wed, 20 Sep 2017 08:14:20 GMT

Here's a (now rather old) script, though you will have to organize your data differently. It was intended to be interactive:

but it would be easy to remove this aspect and make it work for multiple Y's.

Re: How to calculate Area Under the Curve for longitudinal data organized in columns (SPLIT)?

dtp_1997 — Fri, 14 Sep 2018 03:01:58 GMT

I'd like to run the script across multiple response variables (same time scale) then export the results in to a table. How could i do that wiht the existing script? Thanks!

Re: How to calculate Area Under the Curve for longitudinal data organized in columns (SPLIT)?

txnelson — Fri, 14 Sep 2018 16:04:12 GMT

I assume that you have no interest in the left and right edge lines, but actually want the total area under the curve?

Also, would you want to see all of the curves, or just an output table?

I assume you are not familiar with JSL(JMP Scripting Language). But are you familiar with any similar languages?