I want to design a study on hemodialysis patients. I know from basic science knowledge that there are four variables (suppose a, b, c, d) which effect the rates of heart attacks/ strokes and amputation in hemodialysis patients. My objective is to prove that all these have a correlation with heart attacks/ strokes and amputation in dialysis patients. After proving I want to find out which variable has the strongest link with ANY of these events. Now I have 88 dialysis patient in my hospital and have the variable data for a, b, c, d in excel form monthly for 5yrs. How can I use these variables a, b, c, d which will be 12 times in the year and 60 in 5yrs. How is time averaging done?
Let me explain more. I will only take one adverse event heart attack for now. Increase in variable A and B increases risk of heart attack and increase in variable C and D decrease risk of heart attack. How should I design a restrospective study over 5yrs to maximize the chance of finding a significance between the above mentioned hypothesis?
Variables a to d are not binary but rather continuous with limits ofcourse. Example variable C ranges from 1 to 4mg/dl in the blood. The optimum level is 4mg/dl, the lower the level the higher risk of heart attack. Now how should I analyse my data to maximize the chance of finding an association between heart attacks and low level of variable C. I will use the similar strategy for all variables. What test will I use and where can I get the software to do those tests?
I am sorry I dont know the meaning of time average. There is a study that I heard about with a similar idea. They used a variable measured every month for a few years. I am not sure how they time averaged? Perhaps it is the arithmetic mean? This is the study that uses time averaging- Dialysis Modality and Correction of Uremic Metabolic Acidosis: Relationship with All-Cause and Cause-Specific Mortality Tania Vashistha, Kamyar Kalantar-Zadeh. It appeared in the journel CJASN. The link is here- http://cjasn.asnjournals.org/content/early/2012/11/21/CJN.05780612.abstract
Is there a way to attach pdf then I can with this question. Thanks to all in advance