Performance of the EQ-5D in Patients with Irritable Bowel Syndrome

• Published in: Value in health 2006-03, Vol.9 (2), p.90-97
• Main Authors: Bushnell, Donald M., Martin, Mona L., Ricci, Jean-François, Bracco, Andrea
• Format: Article
• Language: English
• Subjects: Adult; Cost-Benefit Analysis; EQ-5D; Female; Germany; Health Status; Humans; irritable bowel syndrome; Irritable Bowel Syndrome - physiopathology; Irritable Bowel Syndrome - psychology; Irritable Bowel Syndrome - rehabilitation; Male; Middle Aged; Pain Measurement; Patient Satisfaction - economics; Patient Satisfaction - statistics & numerical data; Psychometrics - instrumentation; Quality of Life; reliability; Reproducibility of Results; Sickness Impact Profile; Spain; Surveys and Questionnaires; United Kingdom; validity
• ISSN: 1098-3015; 1524-4733
• DOI: 10.1111/j.1524-4733.2006.00086.x

The EQ-5D is a standardized, nondisease-specific instrument for evaluating patients' preference-based valuations of health-related quality of life (HRQoL). This study's purpose was to determine the psychometric properties of EQ-5D in patients with irritable bowel syndrome (IBS). Data from four European IBS studies were assessed: UK (n = 161 and n = 297), Spain (n = 503), and Germany (n = 100). The EQ-5D is a five-item health state descriptive system used to develop health states (EQ-5D INDEX) and a visual analog scale (VAS) (0–100 from worst to best imaginable health state, EQ-5D VAS). Measures used with the EQ-5D included the SF-36, Irritable Bowel Syndrome—Quality of Life (IBS-QOL), and both subjective and clinical global assessments of IBS. Convergent validity was assessed using SF-36 and IBS-QOL data, discriminant validity using global ratings of IBS severity, and responsiveness by subjective and physician assessment of condition. Moderate-to-high associations ( r ≥ 0.33) were seen between the EQ-5D VAS and the SF-36 and IBS-QOL subscales. Mean response scores to EQ-5D INDEX dimensions and the EQ-5D VAS score were significantly better for control patients than for patients with IBS (all P < 0.01). The EQ-5D VAS was able to discriminate between levels of pain severity (quartiles, P < 0.001; mild/moderate/severe, P < 0.05) and general health severity (mild/moderate/severe, P < 0.001). The EQ-5D VAS and the EQ-5D INDEX were responsive in patients using both a self-perceived (Subject's Global Assessment) and physician-rated (Clinic Global Assessment) improvement. The EQ-5D performs well in comparison to general and disease-specific outcomes. It is a valid and responsive measure that can be used to generate preference-based valuations of HRQoL in patients with IBS and useful for comparisons in clinical and cost-effectiveness studies.