I have started a study of record available at clinic collected years back.So it seems to be a retrospective cohort study.But when calculating sample size I feel like it to be done in normal cross sectional way
Under your conditions I would use all the records I had. This is not a sampling situation. D. Booth
Thanks a lot.But won't it affect the power of the study.Of course power would be higher.@David Eugene Booth
No you are dealing with a population NOT a sample if you use all the records as I would advise.
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Pls share your thoughts
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