Development and validation of a specific quality of life module in post-menopausal women with osteoporosis: the QUALIOST.

Established post-menopausal osteoporosis (PMO) has serious consequences on health related quality of life (HRQL), as long-term back and joint pain can severely limit normal activities. The quality of life questionnaire in osteoporosis (QUALIOST), a self-administered module consisting of 23 questions which complements the SF-36, was specifically designed to evaluate the repercussions of PMO on patient HRQL. The QUALIOST was developed simultaneously in French and English after discussion with 45 patients. A validation study in France and the UK included 140 women with PMO, with at least one osteoporotic vertebral fracture. Patients completed the SF-36 and QUALIOST twice, 7 days apart. Factorial analysis revealed a physical and emotional component. Three scores were calculated: physical repercussions (10 items), emotional repercussions (13 items) and the global score (23 items). Internal reliability and stability over time were excellent. Concurrent validity with the SF-36 physical and mental fields was satisfactory. A deterioration in clinical state, as measured by pain severity, hospital admission and walking stick use, increased the repercussions on HRQL for all three scores, demonstrating the clinical validity of the questionnaire. The QUALIOST, combined with the SF-36, is a valid rating scale for measuring HRQL in clinical trials for established PMO, providing both general and specific data on the effects of PMO on patient HRQL.