Use of an Income-Equivalence Scale to Understand Age-Related Changes in Financial Strain.

Income-equivalence scales (IES) provide distinct advantages over poverty indices to adjust family income for differences in family size, including improved specification of hypothesized causal relationships involving objective measures of economic well-being. In a novel IES application, cancer patients' out-of-pocket health costs are adjusted for differences in family income and size and, along with five other subindices, contribute to an overall index of "objective family financial stress." Age-related changes are modeled simultaneously within relationships between overall objective family financial stress and subjective patient perceptions about financial strain. Among the findings, the impact of age on one area of subjective financial strain, "difficulty paying bills," is negative and curvilinear. Regardless of adjusted out-of-pocket costs, as age advances, patients appear increasingly likely to accommodate to financial stress by reporting less difficulty paying bills. This phenomenon could serve to mask and isolate older adults who are foregoing needed yet unaffordable medical care and prescriptions.