Presentation on theme: "American Public Health Association 138 th Annual Meeting Denver, Colorado Nov. 6-10, 2010 The Emerging European Acceptance of Scanlan’s Rule in Health."— Presentation transcript:
American Public Health Association 138 th Annual Meeting Denver, Colorado Nov. 6-10, 2010 The Emerging European Acceptance of Scanlan’s Rule in Health Disparities Research: Will the United States Be Left Behind? James P. Scanlan Attorney at Law Washington, DC, USA email@example.com
Scanlan’s Rule (heuristic rule x, interpretive rule 1) When two groups differ in their susceptibility to an outcome, the rarer the outcome: (a) the greater tends to be the relative difference in experiencing it, and (b) the smaller tends to be the relative difference in avoiding it.
Implications/Illustrations of SR As mortality declines, relative differences in mortality tend to increase while relative differences in survival tend to decrease. As rates of appropriate healthcare increase, relative differences in receipt of appropriate care tend to decrease while relative differences in rates of failing to receive appropriate care tend to increase. Lowering blood pressure generally will tend to increase relative differences in hypertension while decreasing relative differences in rates of avoiding hypertension. Improving overall folate levels will tend to increase relative differences in low folate while reducing relative differences in adequate folate. Among relatively advantaged subpopulations (college-educate, high SES, young) relative differences in adverse outcomes tend to be large while relative differences in favorable outcomes tend to be small. And so on, ad infinitum.
Broader Issues All standard measures of differences between outcome rates tend to be affected by the overall prevalence of an outcome. Disarray and futility in health and healthcare disparities research. Disarray and futility in every other area in the law and the social and medical sciences where differences between outcome rates are a matter of consequence.
References 1 Can we actually measure health disparities? (Chance 2006) Can we actually measure health disparities? Race and mortality (Society 2000) Race and mortality Divining difference (Chance 1994) Divining difference Measurement Problems in the National Healthcare Disparities Report (APHA Conf 2007) Measurement Problems in the National Healthcare Disparities Report Approaches to Measuring Health Disparities that are Unaffected by the Prevalence of an Outcome (APHA Conf 2010) Approaches to Measuring Health Disparities that are Unaffected by the Prevalence of an Outcome
References 2 Pages on jpscanlan.com: Measuring Health Disparities (MHD) (esp. Sec. D and Sec. E7) (and sub-pages) Measuring Health DisparitiesSec. DSec. E7 Scanlan’s Rule (SR) (and sub-pages Scanlan’s Rule Mortality and Survival Measures of Association
Approaches to Disparities Measurement Many researchers: Relative differences in adverse outcomes (especially for mortality and morbidity) or favorable outcomes (especially for health care) NCHS: Always relative differences in adverse outcomes AHRQ: Larger of the two relative differences Health Policy Group of Harvard Medical School: Absolute differences (usually) Harper, Lynch et al.: Value judgment (see Implicit Value Judgments in the Measurement of Health Inequalities (Milbank 2010); Relative Versus Absolute subpage of MHD)Implicit Value Judgments in the Measurement of Health InequalitiesRelative Versus Absolute
Fig 1. Ratio of (1) Disadvantaged Group (DG) Fail Rate to Advantaged Group (AG) Fail Rate at Various Cutoff Points Defined by AG Fail Rate
Fig. 2. Ratios of (1) DG Fail Rate to AG Fail Rate and (2) AG Pass Rate to DG Pass Rate at Various Cutoff Points Defined by AG Fail Rate
Fig. 3. Absolute Differences Between Rates at Various Cutoff Points Defined by AG Fail Rate AB
Fig 4. Ratios of DG Failure Odds to AG Failure Odds at Various Cutoff Points Defined by AG Fail Rate AB
Fig. 5: Ratios of (1) DG Fail Rate to AG Fail Rate, (2) AG Pass Rate to DG Pass Rate, (3) DG Failure Odds to AG Failure Odds; and (4) Absolute Difference Between Rates ● Zone A
Table 1 Illustration Based on Morita et. al. (Pediatrics 2008) Data on Black and White Hepatitis Vaccination Rates Pre and Post School-Entry Vaccination Requirement (see D52 of MHD)D52 PeriodGradeYearWhRtBlRt Fav Ratio Adv RatioAbsDfEES PreRq519968%3%2.671.050.050.47 Post5199746%33%1.322.214.171.124 Post5199850%39%1.2126.96.36.199 PreRq9199646%32%1.441.260.140.37 Post9199789%84%1.061.450.050.24 Post9199893%89%1.041.570.040.26
Table 2 Illustrations Based on Escarce and McGuire (AJPH 2004) Data on White and Black Coronary Procedure Rates, 1986 and 1997 (D48 of MHD)D48 ProcYearWh RtBl Rt Fav Ratio Adv RatioAbsDfEES Angrm19868.56%4.31%1.991.050.040.25 Angrm199722.83%16.10%1.421.090.070.14 Angpls19860.99%0.32%3.091.010.010.32 Angpls19972.57%1.60%1.611.010.010.15 ArtByp19863.06%0.81%3.781.020.020.41 ArtByp19975.86%2.60%2.251.030.030.27
European Recognition of SR Carr-Hill, Chalmers-Dixon (SEPHO Health Inequalities Measurement Handbook(2005): recognizes the theoretical basis of SR Carr-Hill, Chalmers-Dixon Houweling, Kunst, Huisman, Mackenbach (Int J Equity Hlth2007): observationally recognizes patterns of relative and absolute differences. Houweling, Kunst, Huisman, Mackenbach Eikemo Skalicka Avendano (IJEH 2009): observationally recognizes patterns of relative differences Eikemo Skalicka Avendano Bauld, Day, Judge (IJHS 2008): cautious recognition of SR and warning for ignoring it See Section E7 of Measuring Health DisparitiesSection E7
Further Readings Measuring Health Disparities – Solutions Solutions – Relative Versus Absolute Relative Versus Absolute – Concentration Index Concentration Index – Reporting Heterogeneity Reporting Heterogeneity – Pay for Performance Pay for Performance Scanlan’s Rule – Subbgroup Effects Subbgroup Effects – Employment Tests Employment Tests – Illogical Premises Illogical Premises – Case Control Studies Case Control Studies – Case Study Case Study – Meta-Analysis Meta-Analysis