A symptom (for e.g. Headache) can be caused by 2 different diseases (X and Y). Drug “A” acts on both diseases (X and Y). Drug B acts on only second (Y) disease.
Disease “X” patients will be treated with drug “A” ONLY. I want to analyse the effect of only drug “A” on disease “X”.
Disease “Y” patients will be treated with drug “A”, then drug “B” will be added to drug “A”. Then I will be stopping drug “A” while continuing drug “B” only. I want to see if the relief is better or not with a combination of 2 drugs “A and B” on disease “Y” when compared to the effect due to using either drug “A” or drug “B” individually.
The outcome of the treatment will be measured by duration of the headache in decimal hours.
My objective is to study the effect of both drugs on the symptom (for e.g. Headache). Kindly advise me:
How to plan the study
What is the best statistical method with full details.
Can a crossover study be planned and will it be useful? If the answer is yes, kindly guide me with the steps. I am a beginner in statistics.
