How should I analyse this?

#1
Hi everyone,
I'm doing a project where a have a group of patients with a disease X and they will have different treatments overtime.
There are 4 drugs (A, B, C, D) that I am analysing. The outcome is measured in a scale from 1 to 5 (according to how controlled the symptoms are).
Each patient can have a combination of the drugs for a period (and an outcome for this period) and then change for another drug (with a different outcome).

Example:
Patient 1 was treated with drug A + B for 2 years with an outcome of 2. Then he was treated with drug D for 1 year with an outcome of 5.
Patient 2 was treated with drug B for 4 years with an outcome of 1.

...

How is the best way to analyse this study?

How can I consider time and outcome at the same analyses? Is there a way to take advantage of the fact that the same patient might undergo different treatments and have some kind of "paired" analyses?

Thank you very much.
 

Miner

TS Contributor
#2
This appears to be a a type of repeated measures crossover study. I don't know whether the structure of your data will support it, but normally this would be analyzed using a repeated measures ANOVA.
 
#3
This appears to be a a type of repeated measures crossover study. I don't know whether the structure of your data will support it, but normally this would be analyzed using a repeated measures ANOVA.
Thank you for the information.
I just don't understand how I would be able to use the time each patient were under a specific treatment if I used repeated measures ANOVA.
Since each patient can have a different combination of drugs for a different time, is it possible to use this test?
 

Miner

TS Contributor
#4
That's why I said "I don't know whether the structure of your data will support it, ...". I take it that this was not run according to a specific design, but is a retrospective analysis of whatever data is available?
 

Miner

TS Contributor
#6
That will make it trickier. It would probably be some type of regression analysis. Some of the others here may know of better approaches.