The Misinterpretation of Health Inequalities in Nordic Countries James P. Scanlan Washington, DC, USA jps@jpscanlan.com

Mackenbach, Kunst, Cavelaars, et al Mackenbach, Kunst, Cavelaars, et al. Socioeconomic inequalities in morbidity and mortality in western Europe, The Lancet 1997;349: 1655-59: “Sweden and Norway have larger relative inequalities in health than most other countries.”

Interpretive Rule 1(IR1) When two groups differ in their susceptibility to an outcome, the rarer the outcome, (a) the greater tends to be the relative difference in rates of experiencing it, and (b) the smaller tends to be the relative difference in rates of avoiding it.

Implications of IR1 As mortality declines, inequalities in mortality rates will tend to increase (though inequalities in survival rates will tend to decline). For procedures where we measure inequality in terms of relative rates of receipt (e.g., mammography, prenatal care), as the procedures become more universal, inequalities in rates of receiving them will tend to decline (though inequalities in rates of failing to receive them will tend to increase).

Implications of IR1 (cont’d) Because countries like Sweden and Norway have low mortality, they will tend to have large inequalities in mortality rates (though small inequalities in survival rates). Etc.

References “Can We Actually Measure Health Disparities?” Chance, Spring 2006. “Race and Mortality,” Society, Jan-Feb 2000* “Divining Difference,” Chance, Spring 1994. “The Perils of Provocative Statistics,” The Public Interest, Winter 1991* “The Misunderstood Relationship Between Declining Mortality and Increasing Social Differences in Mortality,” Oslo Presentation 2001* “Measuring Health Inequalities,” Athens Presentation 2006* * Available online at jpscanlan.com

Fig.1 – Proportion Disadvantaged Group (DG) Comprises of Total Below Each Cutoff Point

Fig.2 – Ratio of Fail Rate of Disadvantaged Group (DG) to Fail Rate of Advantaged Group (AG)

Fig. 3 – Ratio of Pass Rate of Advantaged Group (AG) to Pass Rate of Disadvantaged Group (DG)

Fig. 4 - Absolute Difference Between Fail (or Pass) Rates of Disadvantaged and Advantaged Groups

Conclusion Not clear whether we can effectively measure changes that are not solely functions of changes in prevalence. Clear that we ought not to be evaluating changes in inequalities without attempting to sort out the role of changes in prevalence.

Supplementary Material Follows

Supp. Fig. 1 – Ratio of Fail Odds of Disadvantaged (DG) Group to Fail Odds of Advantaged Group (AG)

Supp. Fig. 2 – Fail Ratios, Pass Ratios, Odds Ratios