Measuring quality of life today: methodological aspects.

While it is recognized that quality of life is ultimately as important as quantity of life, efforts to implement quality of life measurement often fail. Two basic reasons for that failure include: 1) definitional differences, where different investigators attribute different meaning to the term and, as a result, are measuring different endpoints; and 2) insufficient information about available measures, which can lead to improper test selection and unnecessary regeneration of new items. Included in this paper is a table that reviews many available quality of life measures that have been designed for, or frequently used with, people with cancer. Proper selection of measures and supplementary questions is an important first step toward a successful evaluation of quality of life.