This distinction has important implications for selecting instruments to be used in QOL research. Themajor implication is that questionnaires designed tomeasure health status may be inappropriate for assessing QOL. Several prominent instruments such asthe Health Utilities Index Mark 2 [36], the Quality ofWell-Being Scale [37], and the EuroQol [38] are derived from health utilities or preferences for healthstates ranging from death to optimal functioning.This continuum corresponds more closely to perceived health than to QOL. The same is true for indexes of general health perceptions [39]