Development of a new dyspepsia impact scale: the Nepean Dyspepsia Index

Background: There is not at present a suitable disease-specific health-rela ted quality of life instrument for uninvestigated dyspepsia and functional (non-ulcer) dyspepsia, Aim: To develop a new multi-dimensional disease-specific instrument, Methods: The Nepean Dyspepsia Index (NDI) was designed to measure impairmen t of a subject's ability to engage in relevant aspects of their life and al so their enjoyment of these aspects; in addition, the individual importance of each aspect is assessed, A 42-item quality of life measure was develope d and tested, both in out-patients presenting to general practice with uppe r gastrointestinal complaints (n = 113) and in a randomly chosen population -based sample (n = 347), Results: Adequate face and content validity was documented by an expert pan el, Factor analysis identified four clinically relevant subscales: interfer ence with activities of daily living, work, enjoyment of life and emotional well-being; lack of knowledge and control over the illness; disturbance to eating or drinking; and disturbance to sleep because of dyspepsia, These s cales had high internal consistency, Both symptoms and the quality of life scores discriminated dyspepsia from health. Conclusion: The Nepean Dyspepsia Index is a reliable and valid disease-spec ific index for dyspepsia, measuring symptoms and health-related quality of life.