A brief note on overlapping confidence intervals

Abstract

Clinical researchers frequently assess the statistical significance of the difference between two means by examining whether the two 95% confidence intervals overlap. The purpose of this brief communication is to illustrate that the 95% confidence intervals for two means can overlap and yet the two means can be statistically significantly different from one another at the α = 0.05 level. Copyright © 2002 by The Society for Vascular Surgery and The American Association for Vascular Surgery.