Developing a condition-specific measure of health for patients with dyspepsia and ulcer-related symptoms.

A patient-administered instrument for dyspepsia and symptoms suggestive of duodenal or gastric ulcer, based on the type of questions asked when taking a patient's history, was developed and tested using the following steps: literature reviews, devising the questions, testing the responses to the questions using factor analysis and internal consistency, assessing test-retest reliability, and validating the questionnaire by comparing patient responses to the SF-36 health survey questionnaire. The main sample consisted of 135 patients referred to an outpatient clinic with dyspepsia, and 152 patients in general practice who were not referred to a specialist. The final instrument produced a Cronbach's alpha of 0.72 and an intraclass correlation coefficient of 0.69. Patient scores on the dyspepsia questionnaire had small to moderate correlations with the SF-36 health survey, the largest correlation being with the SF-36 scale of pain. Patient scores were significantly related to general practitioner perceptions of symptom severity, family history of gastric ulcer disease, and whether the patient was referred. The questions asked in taking a clinical history from a patient with dyspepsia and other symptoms suggestive of ulcer disease can be used to construct a valid and reliable measure of the effect of dyspepsia on health.