Validation of a New Measure of Diarrhea

Published In: Digestive Diseases and Sciences, v. 40, no. 9, Sep. 1995, p. 1873-1882

by Howard R. Mertz, C. Keith Beck, Wilfrid Joseph Dixon, A Esquivel, Ron D. Hays, Martin F. Shapiro

Presents a visual system designed to characterize diarrhea from the perspective of HIV-infected patients. Using pictorial representations from six stool forms, varying from solid to completely liquid, and a battery of self-report items, the authors developed a questionnaire to assess diarrhea severity and complications in symptomatic patients with HIV-related illness. Self-reported diarrhea correlated with the occurrence of any stool pictured without form. However, patients showed wide variability in selecting pictures of stools described as loose or semi-formed. Both verbal and pictorial descriptors correlate well with diarrhea complications (pain, incontinence, nocturnal diarrhea). The authors conclude that they have developed an instrument to characterize diarrhea severity that correlates well with clinically important events such as incontinence and abdominal pain.

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