Methodological issues in measuring health-related quality of life

Modern medicine has made significant progress in screening, diagnosis, and treatment, but the objectives of treatment have been a subject of debate. The question “Should the focus be on the quantity or on the quality of survival?” still prevails Nowadays, health-related quality of life (HRQOL) has become an important index in medical treatment and clinical care. The health care system focuses on improvement in quality of life and health which are influenced by illness. The emphases of this article are on the definition and concepts of HRQOL. We discuss the methodological issues in the measurement of HRQOL including: (1) objectivity versus subjectivity, (2) generic versus specific, (3) unidimensional versus multidimensional, (4) self-report versus proxy report, (5) reliability, (6) validity, and (7) the selection of HRQOL measures. Subsequently, the importance of HRQOL in the treatment of a disease is also addressed.