Alternative definitions of disability: relationship to health-care expenditures.

The purpose of this study is to investigate the relationship between different definitions of disability and health-care expenditures in the working aged population in the United States using the 1987 National Medical Expenditure Survey (NMES). Five different definitions of disability were identified and the health-care expenditures for each group were compared using descriptive analyses. Results reveal that estimates of the prevalence of disability vary dramatically by the definition of disability. A more than three-fold difference in average total health-care expenditures is observed using different specifications of disability. These results suggest that estimates of health-care expenditures should be interpreted cautiously, since the definition influences the magnitude of estimates. Researchers and policy-makers should consider the standardization of the term 'disability'.