2.2 Sample size calculation A. Diagnostic part Based on the binomial distribution, at an expected sensitivity of 97% with a minimal acceptable lower confidence limit of 85%, the minimal number of cases is 59, not taking into account the non-monotonic nature of power as a function of sample size due to discreteness of the binomial distribution.[17] The number of controls, derived through the formula Ncontrols =Ncases [(1-Prev)/Prev],[18] is 7316 at a prevalence of 0.8% and 6497 at a prevalence of 0.9%.