Defining And Measuring Disparities, Inequities, And .

Defining and measuringdisparities, inequities, andinequalities in the HealthyPeople initiativeRichard Klein MPH, David Huang, Ph.D.National Center for Health StatisticsCenters for Disease Control and Prevention

Four Concepts of DifferenceDisparityInequityInequalityBurden

Distinctions Among the ConceptsConceptResearch questionApplication to policy orprogram planningDisparityIs there a difference in health statusrates between population groups?Is the difference too large?InequityIs the disparity in rates due todifferences in social, economic,environmental or healthcareresources?Is the distribution of resources fair?How do rates vary with the amount ofthe resource, and how is thepopulation distributed amongresource groups?Can the distribution of the populationamong resource groups and/or the rateswithin resource groups be influenced?How many people are affected inspecific groups and in the totalpopulation?How many people would benefitfrom interventions?Inequality*Burden*Questions and applications refer to ordered groups

The Concept of DisparityDisparity is the quantity that separates a groupfrom a reference point on a particular measure ofhealth that is expressed in terms of a rate,proportion, mean, or some other quantitativemeasure. (HP2010)

Disparity in Healthy People 2010( and implict value judgments*) Disparities are measured from the mostfavorable group rate, (Preference for raising healthamong unhealthy groups) in terms of relative differences, (Equality valued overpopulation health or rates of disease) with groups unweighted for size (Groups are of equalimportance regardless of size) Disparity across domains is measured by averagedifference (Emphasis on reducing inequality regardless of how)**Based on Harper et al Implicit Value Judgments in the Measurement of Health Inequalities. The Milbank Quarterly, Vol. 88, No. 1 (pp. 4–29). 2010

Infant Mortality Rates per 1,000 Live Births byMother’s Education, US 2005EDUCATIONRATE0-8 years9-11 years12 years13-15 years16 years or more6.69.38.16.14.2Source: National Vital Statistics System (NVSS), CDC, NCHS.A difference in disparity For example—The infant mortality rate for mothers with 911 years of education is 5.1 infant deaths per 1,000 livebirths (or 121%) greater than the rate for mothers with 16or more years of education.

The Concept of Health EquityHealth equity is the fair distribution of healthdeterminants, outcomes, and resources within andbetween segments of the population, regardless ofsocial standing.Working definition from the CDC Health Equity Working Group, October2007

The Concept of InequityInequity A difference in the distribution or allocation of aresource between groups (usually expressed as groupspecific rates) Resources relevant to health include:Health insurance Education Flu vaccine Fresh food Clean air

Percent of mothers with 12 or more years ofeducation, by race/ethnicity, U.S. 2005Race/EthnicityAmerican Indian or Alaska NativeAsian or Pacific IslanderHispanicBlack non-HispanicWhite non-HispanicPercent70.290.752.777.189.3Source: National Vital Statistics System (NVSS), CDC, NCHS.Inequity question: Are the racial/ethnic differences in infant mortality ratesthat we observe attributable to educational differences? Are those differences “fair”?

The Concept of InequalityInequality A measure of the degree of association betweendifferences in rates between groups and thedistribution of the population among groups It is a single value that represents The degree of association between rates for a healthindicator and the distribution of the population amongordered groups (education and income)-or The degree of variation in rates among unorderedgroups, weighted by group size (race and ethnicity)

Educational inequality in infant mortalityfor white non-Hispanic mothers, U.S. 200510869-11 yearsInfant deaths per 1,000 live births12420-8 years12 years13-15 years27.9%24.0%9.1%16 yearsyears andand overover1637.4%35.5%1.6%00204060Cumulative percent of the population80100 The slope index of inequality -7.3. The infant mortality rate declines byan average of 7.3 infant deaths per 1,000 live births over this population,ordered by years of education.Source: National Vital Statistics System (NVSS), CDC, NCHS.

Educational inequality in infant mortalityfor Hispanic mothers, U.S. 200510812 years16 years 613-15 yearsInfant deaths per 1,000 live births1230.6%13.7%8.4%40-8 years9-11 years220.8%26.50020406080100Cumulative percent of the population The slope index of inequality -1.1. The infant mortality rate declines byan average of 1.1 infant deaths per 1,000 live births over this population,ordered by years of education.Source: National Vital Statistics System (NVSS), CDC, NCHS.

The Concept of BurdenA difference in burden The difference in the number of persons affectedbetween groups. Generally, the larger the group—the larger theburden.

Number of Infant Deaths by Mother’sEducation, US 2005EDUCATIONNUMBER0-8 years9-11 years12 years13-15 years16 years or moreNot stated1,1453,8366,7473,6663,231994Source: National Vital Statistics System (NVSS), CDC, NCHS.A difference in burden For example—The burden of infant deaths is greatest formothers with 12 years of education.

Burden of infant deaths and reduction in burden,by race/ethnicity of mother, U.S. 2005Infantdeathsper 1,000live birthsBurden(number ofinfant deaths)Population by race and ethnicityNon-Hispanic blackAmerican Indian or Alaska NativeNon-Hispanic whiteHispanicAsian or Pacific Islander (best 28,119Reduction in burden(number of infant deaths)If HP targetIf disparities achieved witheliminatedno change 13839,556Source: National Vital Statistics System (NVSS), CDC, NCHS.HP2010 objective: reduce the infant mortality rate to 4.5 infant deaths per 1,000 live births

Disparity/Inequity in Healthy People 2020 What was called disparity (i.e. difference) inHP2010 is increasingly being called “inequality”(Harper et al, Pokras et al) The concept of disparity in HP2020 is closer toprevious conceptions of inequity:Health disparity: A particular type of health difference that is closelylinked with social or economic disadvantage . Health disparitiesadversely affect groups of people who have systematically experiencedgreater social or economic obstacles to health based on their racial or ethnicgroup, religion, socioeconomic status, gender, mental health, cognitive,sensory, or physical disability, sexual orientation, geographic location, orother characteristics historically linked to discrimination or exclusion.

The Concept of Health Equity“Health equity is a desirable goal/standardthat entails special efforts to improve thehealth of those who have experienced socialor economic disadvantage”Source: Secretary’s Advisory Committee on National Health Promotion andDisease Prevention Objectives for 2020

Summary There are multiple, valid methods for assessingdifferences in health between population groups Selection of specific methods implies value judgmentsand methods can often come to contradictoryconclusions Terminology is evolving and is not always usedconsistently by all researchers The approach for Healthy People is moving frommeasuring bivarate differences to also consideringequity/fairness and univariate approaches. Thispresents serious methodological/measurementchallenges

The goal to eliminate disparitiesremains undefined.When is a disparity eliminated?When has parity been reached?When has health equity beenachieved?

Educational inequality in infant mortality for white non-Hispanic mothers, U.S. 2005. Infant deaths per 1,000 live births. Cumulative percent of the population. 16 years and over 9- 12 years 13-15 years 11 years 0-8 years. 1.6% 9.1% 27.9% 24.0% 35.5%. 16 years and over. 37.4%. 0 2 4 6 8 10 12 0 20 40 60 80 100 The slope index of inequality -7.3.