A comparison of self-reported measures of perceived health and functional health in an elderly population.

In studies of large elderly populations, two types of measures of physical health status, perceived health and functional health, are commonly used. Although they represent very different conceptions of health, these two types of measures appear often to be used interchangeably. In this paper, we examine changes over time in self-reported measures of perceived health and functional health for a sample of Medicare beneficiaries. By investigating the patterns of change in the two measures for different subgroups of the population, we are able to draw inferences about the appropriateness of each type of measure for specific administrative and/or research situations. The perceived health status measure appears suitable for descriptive studies of the health of elderly populations, while the greater stability of functional health makes this type of measure generally more appropriate in studies investigating relationships between an individual's physical health status and subsequent behavior.