To the Editor: In the article on prophylactic sclerotherapy (March 31 issue),1 it may be true that sclerotherapy had no effect, but Santangelo et al. have not adequately eliminated the possibility that a Type II error accounted for the negative results. We must take exception to the calculations of the authors regarding the power of the study. In the Methods section of their article they state that 74 patients would be required to demonstrate a 50 percent reduction in the bleeding rate with sclerotherapy, assuming that 40 percent of the patients in the control group bled — a statistical power.
ASJC Scopus subject areas