CRH and Cowden syndrome 1: Different study protocols (number and time of dex doses, ovine vs human CRH at fixed/weight-adjusted doses), different accuracy of cortisol assays for low levels, concomitant medications, even without measurement of serum dex, and differences in the enrolled population (number of cases, severity of hypercortisolism, subtypes of CS and NNH/pCS) can all contribute to different results [5].