Sample Size for Paired Cohort Studies


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This function gives you the minimum number of subject pairs that you require to detect a true relative risk RR with power POWER and two sided type I error probability ALPHA (Dupont, 1990; Breslow and Day, 1980).


Information required


Practical issues


Technical validation

The estimated sample size n is calculated as:

- where α = alpha, β = 1 - power and zp is the standard normal deviate for probability p. n is rounded up to the closest integer.



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