Measuring quality of life in dyspeptic patients: Development and validation of a new specific health status questionnaire - Final report from the Italian QPD Project involving 4000 patients

OBJECTIVE: Despite the fact that gastrointestinal disorders represent one o f the most common reasons for medical consultations, formal assessment of p atients' health-related quality of life (HRQOL) has been carried out only i n a few studies, and in most cases generic questionnaires have been adopted . Because the specific issue of living with dyspeptic problems has been add ressed in very few cases and no questionnaire has been shown to be appropri ate for the Italian setting, a prospective project was launched to develop a specific HRQOL questionnaire for dyspepsia sufferers tailored to Italian patients but also appropriate in other cultural settings. METHODS: The project consisted in a 3-yr, three-phase survey, in which diff erent versions of the quality of life in peptic disease questionnaire (QPD) were developed through expert and patient focus groups and empiric field s tudies and then administered to patients recruited in five multicenter stud ies. Standard psychometric techniques were used to evaluate the validity, r eliability, responsiveness, and patient acceptability of the QPD. RESULTS: Three different versions of the QPD questionnaire were self-admini stered to more than 4000 patients. The final 30-item version, measuring thr ee health concepts related to dyspeptic disease (anxiety induced by pain, s ocial restriction, symptom perception), fulfilled the recommended psychomet ric criteria in terms of reliability and validity, correlated with health c oncepts measured with a well-known independent generic HRQOL instrument (th e SF-36 Health Survey questionnaire) and was relatively invariant to diagno sis and sociodemographic variables; it also correlated with a measure of ga stric pain frequency and was able to detect meaningful differences over tim e. CONCLUSIONS: Although further validation studies in different cultural and linguistic settings are mandatory before any firm conclusions can be drawn regarding the crosscultural validity of the QPD, the data obtained provide evidence of the psychometric validity and robustness of the questionnaire w hen used in a fairly large, well-characterized population of Italian dyspep tic patients. (Am J Gastroenterol 1999;93:730-738. (C) 1999 by Am. Coll. of Gastroenterology).