Validation of a new measure of diarrhea.

Adequate measures of diarrheal disease are important to assess severity for clinical use and outcomes research. We developed a questionnaire to assess diarrhea severity and complications, and administered it to 205 HIV positive patients with diarrhea, fever, or weight loss. Noteworthy variations in stool form were reported by individuals and across subjects. Self-reported diarrhea correlated with the occurrence of any stool pictured without form. However, verbal descriptors "loose" and "semiformed" had little value in assessment of diarrheal disease. Both verbal and pictorial stool descriptors correlated well with diarrhea complications (pain, urgency, tenesmus, incontinence, and nocturnal diarrhea). By factor analysis, discomfort and nondiscomfort diarrhea complications loaded on different factors, consistent with clinical experience that discomfort is a distinct problem in diarrheal disease. In summary we have developed an instrument to precisely characterize diarrhea severity that correlates well with clinically important events such as incontinence and abdominal pain.