16. Recent studies using a global approach to measuring illness.

Global measures of illness are designed to measure the performance of a health service as a whole and the contribution of its various components. Such measures convert data about the outcome of medical care into information for use in planning at all administrative levels including the highest levels of government. This is achieved by means of a classification of states of illness applicable to all patients, whatever their diagnosis and symptoms, and of a scale which places valuations as perceived by society on the defined states. The valuations of changes in the states of individuals during treatment or over a period of time can then be summed for heterogeneous populations. By adjusting the valuations of future changes for time preferences it may be possible to take into account prognosis, and by placing a valuation on death, mortality and morbidity data can be combined. The properties appropriate to the classification and scale are defined and problems encountered in their derivation are discussed. Examples are presented of the application of one global measure to a group of medical specialists and to population data for the United Kingdom.