CRITICAL-REVIEW OF THE INTERNATIONAL ASSESSMENTS OF HEALTH-RELATED QUALITY-OF-LIFE

This paper reviews the international adaptation and use of generic hea lth quality of life measures over the last several years, including th e Nottingham Health Profile (NHP) the Sickness Impact Profile (SIP), t he Medical Outcomes Short-Form 36 (MOS SF-36), the EuroQol, and Dartmo uth COOP Charts. International work with disease or condition specific HRQL measures is exemplified with the European Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ), and the Spitze r Quality of Life (QL) Index. Progress towards cross national measurem ent equivalence in HRQL measures reported in the literature has been u neven. Results show that the development of language-adapted versions of HRQL measures to date have mostly concerned translation issues, wit hin the context of independently conducted studies. Substantially less focus has been placed on psychometric equivalence across language ver sions necessary for coordinated international studies, such as multi-n ational clinical trials. However, this picture is rapidly changing wit h recent projects underway to develop and refine new or existing HRQL measures. Overall, the lack of prominent differences found between cou ntries in ranking of health states in major HRQL measures supports the feasibility of developing internationally applicable HRQL instruments . Recommendations are made for additional date needed to better ascert ain the degree of measurement equivalence developed in the various ver sions of each instrument reviewed.