ITT (Intention to treat) statistical analysis in clinical trials

[anil]

Dear all,
As I am rather new to SAS, I require help (reference) in understanding ITT LOCF(Last Observation Carried Forward) method.
Thanks

[RolandRB]

> Dear all,
> As I am rather new to SAS, I require help (reference)
> in understanding ITT LOCF(Last Observation Carried
> Forward) method.
> Thanks

You will need to check on this but ITT is the Intent-to-Treat population. This should be a variable flagged for each patient who is a member of this population. Having subsetted on this population then LOCF is a post-baseline value that gets "carried forward" to fill any gaps for values not recorded and to carry on the last non-missing value until the end of the period of interest (such as the length of the study) even if the patient dropped out before the end of this period.

Again, you need to understand what you are doing and it could be that several values are carried forward and "last observation" carried forward does not mean "last SAS dataset observation". Bearing in mind that you must make the effort to understand what you are doing, I have a page on LOCF processing that you can read here and you can also download the macro.

http://www.datasavantconsulting.com/roland/spectre/locf.html

[anil]

Thank u for ur excellent reply.
Veri much satisfied with the information. I will email u on specific problem.
Thanx