An analysis of the changes in health risk appraisal technology and epidemiology: Its impact on worksite health promotion programs and evaluation
The composite health risk measure of health age created by the 1984 CDC version 2.0 software was compared with the health age measure created by the 1991 Healthier People version 4.0c software. It was hypothesized that there would be significant differences between the measures of health age as created from the different technologies, however, the direction of these differences was not specified. No specific hypothesis was postulated as to what health risk characteristics would be most influential in either the calculation of the health age measure, or the change of this measure over time. Baseline measures of health age between technologies were significantly different (t(284) = $-$6.70, p $<$.000), while retest measure showed no difference (t(284) = $-$.04, p $<$.971). The health age measure derived from the 1991 technology indicated a significant reduction in health age over time (t(284) = 13.27, p $<$.000), while the 1984 health age measure showed marginally significant change from baseline to retest (t(284) = 1.88, p $<$.061). Multivariate linear models were created for predicting the retest measure of health age from both technologies. Both equations account for over 96% of the variance in health age and show significant linear relationships among the variables (F(284) = 294.75, p $<$. 001 for the 1984 equation and (F(284) = 346.11, p $<$.001 for the 1991 equation). Exercise accounted for the most significant incremental change in the prediction model for the 1984 technology, as compared to systolic blood pressure for the 1991 technology. It is difficult, if not impossible to predict or specify a consistent difference in the actual health age measure resulting from these differences in technology alone. Health age differences are a result of the complex interaction of health risk characteristics within a population under study and the associated mix of changes to these characteristics as a result of some intervention. In general, the 1991 Healthier People health age measure will be more influenced by a few modifiable risk factors such as blood pressure, cholesterol, smoking-related indicators, and non-modifiable risk factors such as diabetes, when compared to the 1984 CDC health age measure.