The Race and Health Initiative announced by President Clinton in February 1998 included immunization as one of its six focus areas. In October of that year, the Department of Health and Human Services issued a two-page report styled “Progress Review: Black Americans” discussing various health disparities issues. One area where the report was able to report notable progress involved immunization, the single focus area of the initiative that involved healthcare rather than health itself. The report cited reductions in racial differences in both pneumococcal and influenza immunizations among older adults. For the former, while the black and total rates had been 6% and 15% in 1989, they were 23% and 34% in 1995. For the latter, while the black and total rates had been 20% and 33% in 1989, they were 40% and 58% in 1995.
Based on the way the difference was typically calculated (with the disadvantaged group’s rate as the numerator of a fraction), these figures indicated substantial narrowing of the immunization gaps. For pneumococcal immunization, the relative difference between the rates had decreased 60% in 1989 to 32.4% in 1995, a decline of almost half. For influenza vaccination, the relative difference had decreased from 39.4% in 1989 to 31% in 1995, a decline of about one-fifth. These figures are shown in the Rel Im Df Column in Table 1 below.
Table 1: Changes in Total and Black Pneumococcal and Influenza Vaccination Rates Report in 1998 Progress Review
Rel Im Df
Rel No Im Df
The measuring of immunization disparities based on relative differences in immunization rates is also the method used in the 2008 study by Morita et al., which is discussed in the main Immunization Disparities page.
Commencing in 2004, however, the National Center for Health Statistics would have measured disparities in terms of relative differences in failure to be immunized, which differences are shown in the Rel No Im Df column. Thus, NCHS would have found the pneumococcal immunization disparities to have increased by 57% and the influenza immunization disparities to have increased by 120%.
The Centers for Disease Control and Prevention, which measures disparities in terms of absolute differences between rates (the AD column), would have regarded both disparities to have increased, a 22% increase for pneumococcal immunization and a 38% increase for influenza immunization.
The Agency for Healthcare Research and Quality, which measures disparities in terms of whichever relative difference is large, would have found the pneumococcal immunization disparities to have decreased substantially. It is not clear how AHRQ would have regarded the influenza immunization disparities to have changed. For the relative differences in receipt of immunization (which was larger in 1989) decreased substantially, while the relative difference in failure to be immunized (which was the larger of the two relative differences in 1995), increased substantially.
The final column, EES for estimated effect size which reflects a measure of difference unaffected by the change in the prevalence of the outcome Solutions sub-page of Measuring Health Disparities, indicates that the pneumococcal immunization disparity decreased substantially while the influenza immunization disparity increase modestly.