Psychiatric Illness and Contraction Abnormalities of the Esophagus

To the Editor: Clouse and Lustman's report in the December 1 issue concluded that "psychiatric illness is associated with a specific cluster of esophageal contraction abnormalities."¹ However, the authors did not test the alternative hypothesis that psychiatric illness and esophageal contraction disorders are associated because both are related to a patient's sex. Despite mentioning this possibility in the Discussion, they ignored their own data by collapsing a three-way contingency table (esophageal contraction abnormalities by psychiatric illness by sex) into a two-way table (esophageal contraction abnormalities by psychiatric illness).Examining their data reveals that sex successfully predicts 68 per cent of . . .