# Presentation: 202166

## Measuring DisparitiesIn Health

- Concurrent Session III – 12
- Monday, July 15th  3:30 – 5:00 PM

## What Do We Mean By Disparity

- Jeffrey N. Pearcy, MS
- Kenneth G. Keppel, PhD

- National Center for Health Statistics

**Notes:**
It is said that familiarity breeds ... complacency...

Discussion of disparity has become very familiar.   The concept seems very simple and straightforward, so much so that we may forget what its components are

## Disparity

- Public Health context

**Notes:**
 In the context of public health , the term Disparity takes additional meaning compared to its use in other biological and physical sciences.

 (a) Disparity is defined as marked or pronounced (**how big**) inequality, but has in context come to mean  disadvantaged, inequitable, and unjust.
    (b) As such, it follows to form an operational definition of disparity in public health that includes elements of both Inequality and Inequity.

## Disparity

- Public Health context
- Composed of Inequality and Inequity

**Notes:**
 In the context of public health , the term Disparity takes additional meaning compared to its use in other biological and physical sciences.

 (a) Disparity is defined as marked or pronounced (**how big**) inequality, but has in context come to mean  disadvantaged, inequitable, and unjust.
    (b) As such, it follows to form an operational definition of disparity in public health that includes elements of both Inequality and Inequity.

3) That it is important to bear in mind the distinction between the two terms has been noted recently in several venues;
(a) The distinction was made by George Allenyne of the PAHO at the 1998 APHA, and is included in the PAHO methodological summary on measuring 	Inequity in Health (Epiedemiological Bulletin, Vol. 20 No.1, March 1999).
(b) The distinction between Inequality and Inequity was included as a Doctoral course in the University of Michigan, School of Social Work.  
(c) And more recently been advocated by Paula Braveman at the 2001 APHA meeting.

## Disparity

- Public Health context
- Composed of Inequality and Inequity
- “..Inequality
- A factual matter
- Inequity
- An ethical judgement..”
- (Roy Carr-Hill, U.K. Health Equity Network)

**Notes:**
 In the context of public health , the term Disparity takes additional meaning compared to its use in other biological and physical sciences.
 (a) Disparity is defined as marked or pronounced (**how big**) inequality, but has in context come to mean  disadvantaged, inequitable, and unjust.
    (b) As such, it follows to form an operational definition of disparity in public health that includes elements of both Inequality and Inequity.
3) That it is important to bear in mind the distinction between the two terms has been noted recently in several venues; (a) The distinction was made by George Allenyne of the PAHO at the 1998 APHA, and is included in the PAHO methodological summary on measuring Inequity in Health (Epiedemiological Bulletin, Vol. 20 No.1, March 1999).  (b) The distinction between Inequality and Inequity has included as a Doctoral course in the University of Michigan, School of Social Work.  (c) And more recently been advocated by Paula Braveman at the 2001 APHA meeting.
4)The distinction was made succinctly by Roy Carr-Hill, of the UK Health Equity Network “We also have to be beware of confusing the measurement of Inequality with the measurement of Inequity.  The former is a factual matter, the latter is an ethical judgment.”

5)Inequality is a factual matter
Inequity is this, but also a value-based, ethical judgment that the inequality – the health differential is unfair and unjust.

## Components of Disparity

- Inequality
- How different are we?
- (measurement issues)
- Inequity
- Who should we be like?
- (another group)
- What should we be like?
- (some target)

**Notes:**
1) So, Inequality goes to the question of:  “How different are we?”.  
Measuring this difference can take a number of forms, but can be dealt with in an objective way, by taking differences, ratios, averages, etc.

2) In contrast, Inequity requires a decision about how much a difference should be reduced.  Whether that is in terms of which other group one should be like, or, in absolute terms, what level of outcome should be attained.

## Perspective

- Inequality
- How different are we?
- Are different outcomes unavoidable?
- ......or,
- Are different outcomes avoidable?

**Notes:**
Assuming that Disparity in the context of public health can be decomposed into   Inequality  and  Inequity;

The model can be further extended to evaluate  Inequality in terms of whether the differences are  Avoidable  or Unavoidable

*****
It is important to carefully consider whether disparities are avoidable or not.  On the one hand, it can be viewed as desirable or necessary that all health differentials are avoidable or potentially avoidable.  And that the strength of this policy perspective will serve as a (catalyst) for action.  On the other hand, it should be clear that in the short-term (time?) many health disparities ARE unavoidable.  A number of chronic diseases (which?) have such large existing differentials, and have such substantial lag times between intervention and outcome that rapid change is not possible.  **more??** 

## Perspective

- Inequity
- Outcomes are avoidable
- Are differences acceptable?
- ....or,
- Are they unfair and unjust?

**Notes:**
Next,  if it can be determined whether differences are avoidable, 

then the question of  Inequity  can be addressed by deciding whether differences are acceptable or not.

## Disparity Evaluation

- Adapted from Evans, Whitehead, Diderichsen, et al.  2001

**Notes:**
Consider Disparity in terms of a decision tree.  -  Ideally, this is the type of approach that should be taken

First, a determination of whether two or more groups are different must be made.  We have many statistics to do this (absolute diff., % diff, ratio, etc.),  but the most appropriate may not be readily apparent.  This problem, the selection of statistics, will be introduced in the presentations that follow. 

A question that should also be asked at this point is “how different are these?”  - - how big is the difference?   And does the difference rise to the level of disparity.  In that we have no guidelines in this matter, it may not be easy to determine.  That is, is the difference significant or important?

Next, we could ask a series of questions as to whether the inequality is unavoidable or potentially avoidable.  This could be made on the basis of (Whitehead’s, Braverman’s, others??) health determinants, or others

Finally, an ethical judgment of whether a real inequality, that is potentially avoidable, is acceptable, or whether it is unfair and unjust.

## Determinants of Disparity

*           *_***Unavoidable***_
- Genetics
- Unhealthy behavior – freely chosen
- Temporary health advantage

- Adapted from Margaret Whitehead,  1992

**Notes:**
Genetics
Some determinants of health differentials are for the most part - unavoidable, such as those related to genetics.  Some, are well understood; those related to one or few genes such as (cystic fibrosis, sickle cell anemia, polycystic kidney disease, hemophilia, etc.)

Other diseases may have multiple genetic factors, and span multiple alleles.  They may be differentially expressed in response to environmental influences, and this may vary in prevalence depending on race, ethnicity, or cultural background.  
For example, White non-Hispanics may be more genetically predisposed to melanoma than other R/E groups.  
Or, populations of northern European extraction, which are more susceptible to multiple-sclerosis than African or Asian groups (Oksenberg – 1996, 1998) 
And, non-diabetic kidney disease ocurring twice as frequently among black non-Hispanics compared to other R/E groups (Winkler 1998?)

Gene therapy (e.g. dose-specific prescription of warfarin for liver disease [based on 1 of 3 alleles] holds some promise, but becomes prohibitively expensive when many genes are involved.  Therapy that involves alteration of the genome is both controversial, and in the distant future.

Or, through the process of aging the elderly die of coronary heart disease at higher rates than the young.

## Determinants of Disparity

*           *_***Unavoidable***_
- Genetics
- Unhealthy behavior – freely chosen
- Temporary health advantage

- Adapted from Margaret Whitehead,  1992

**Notes:**
Behavior

Similarly, unhealthy behavior choices made in diet and activity may lead to adverse health outcomes. 
An example might be participation in extreme sports leading to higher injury rates in one group compared to another.  

Or,
Unhealthy choices in diet that lead to obesity.

A lot of effort has been given to these areas in terms of education and intervention, but as long as free choice remains, from a public policy perspective, may be considered, or prove to be unavoidable.

** more about LACK of free choice later***

Whitehead also notes a transient health advantage.  If one group takes up a healthier behavior before, or in greater relative numbers than another group (such as bicycle helmet use) a disparity may develop.  But, it could be considered unavoidable as long as the other group was not disadvantaged in its means to catch up.

## Determinants of Disparity

*           *_***Unavoidable***_
- Genetics
- Unhealthy behavior – freely chosen
- Temporary health advantage

- Adapted from Margaret Whitehead,  1992

**Notes:**
Similarly, unhealthy behavior choices made in diet and activity may lead to adverse health outcomes. 
An example might be participation in extreme sports leading to higher injury rates in one group compared to another.  

Or,
Unhealthy choices in diet that lead to obesity.

A lot of effort has been given to these areas in terms of education and intervention, but as long as free choice remains, from a public policy perspective, may be considered, or prove to be unavoidable.

Temporary Health Advantage

Whitehead also notes a transient health advantage.  If one group takes up a healthier behavior before, or in greater relative numbers than another group (such as bicycle helmet use) a disparity may develop.  But, it could be considered unavoidable as long as the other group was not disadvantaged in its means to catch up.

## Determinants of Disparity

-                  _***Avoidable***_
- Restricted lifestyle choices
- Damaging environment
- Access to care
- Natural selection

- Adapted from Margaret Whitehead,  1992

**Notes:**
Behavior – Not freely chosen
Determinants are avoidable  as when there are restricted choices in health-promoting behavior.  A good example is that of unhealthy diet for groups that have low incomes, or live in areas with restricted availability of nutritious foods.  Or when products such as tobacco or alcohol are targeted at specific groups.

Environment
Also, if some group is restricted by income, or some other reason to living unsafe housing, or to working in more dangerous occupations we should consider this to be avoidable.

Access to Care
Differentials in access to care are clearly avoidable – it is rarely a matter of choice to seek out less or inadequate care.

Natural Selection
Natural selection refers to the type of situation characterized by loss of job or reduction in income, followed by reduced access to care and possibly illness, that in turn affects the ability to be able to work and afford care.

## Determinants of Disparity

-                  _***Avoidable***_
- Restricted lifestyle choices
- Damaging environment
- Access to care
- Natural selection

- Adapted from Margaret Whitehead,  1992

**Notes:**
Behavior – Not freely chosen
Determinants are avoidable  as when there are restricted choices in health-promoting behavior.  A good example is that of unhealthy diet for groups that have low incomes, or live in areas with restricted availability of nutritious foods.  Or when products such as tobacco or alcohol are targeted at specific groups.

Environment
Also, if some group is restricted by income, or some other reason to living in unsafe housing, or to working in more dangerous occupations we should consider this to be avoidable.

Access to Care
Differentials in access to care are clearly avoidable – it is rarely a matter of choice to seek out less or inadequate care.

Natural Selection
Natural selection refers to the type of situation characterized by loss of job or reduction in income, followed by reduced access to care and possibly illness, that in turn affects the ability to be able to work and afford care.

## Determinants of Disparity

-                  _***Avoidable***_
- Restricted lifestyle choices
- Damaging environment
- Access to care
- Natural selection

- Adapted from Margaret Whitehead,  1992

**Notes:**
Behavior – Not freely chosen
Determinants are avoidable  as when there are restricted choices in health-promoting behavior.  A good example is that of unhealthy diet for groups that have low incomes, or live in areas with restricted availability of nutritious foods.  Or when products such as tobacco or alcohol are targeted at specific groups.

Environment
Also, if some group is restricted by income, or some other reason to living unsafe housing, or to working in more dangerous occupations we should consider this to be avoidable.

Access to Care
Differentials in access to care are clearly avoidable – it is rarely a matter of choice to seek out less or inadequate care.

Natural Selection
Natural selection refers to the type of situation characterized by loss of job or reduction in income, followed by reduced access to care and possibly illness, that in turn affects the ability to be able to work and afford care.

## Determinants of Disparity

-                  _***Avoidable***_
- Restricted lifestyle choices
- Damaging environment
- Access to care
- Natural selection

- Adapted from Margaret Whitehead,  1992

**Notes:**
Behavior – Not freely chosen
Determinants are avoidable  as when there are restricted choices in health-promoting behavior.  A good example is that of unhealthy diet for groups that have low incomes, or live in areas with restricted availability of nutritious foods.  Or when products such as tobacco or alcohol are targeted at specific groups.

Environment
Also, if some group is restricted by income, or some other reason to living unsafe housing, or to working in more dangerous occupations we should consider this to be avoidable.

Access to Care
Differentials in access to care are clearly avoidable – it is rarely a matter of choice to seek out less or inadequate care.

Natural Selection
Natural selection refers to the type of situation characterized by loss of job or reduction in income, followed by reduced access to care and possibly illness, that in turn affects the ability to be able to work and afford care.

## Applications of Disparity Model

- Inequality
- Descriptive or Monitoring
- Inequity
- Goal or Target Oriented

**Notes:**
A disparity model based on Inequality is very straightforward, and is implemented regularly – that is, measuring how different one group is from another.

However, a disparity model that includes Inequity is complex.  And requires a series of objective evaluations for which there may not always be data.  It also requires a subjective judgment of what is unfair and unjust.

Alternatively, a simplified Disparity model may be used that assumes all health differentials are avoidable, and that all are unjust.

## Conclusions

- Disparity...not so simple after all !!
- Inequality   ==   Inequity
- Complex interactions of ...
- Genetics
- Environment (physical, social, economic)
- Behavior

**Notes:**
In closing, if Disparity and its measurement is viewed broadly – inclusive of determinants of health, and the recognition of the difficulty of making objective, or even reasonable judgments about what is unfair or unacceptable – it should be apparent that it is not so simple at all.

It should be kept in mind that Inequality is not the same thing as Inequity.  As discussed earlier they should be seen as different in application to public health.

Effective methods to reduce and eliminate all disparities do not exist.  Functional pathways leading to health disparities are directed by the complex interactions of Genetics, the Environment, and Behavior.  Although the ability to measure these is improving, the understanding of how they interact is only beginning to be understood.

## Conclusions

- Incomplete knowledge  ==  Inaction !
- Purposes of measurement
- Monitoring and Assessment
- Intervention and Improvement Programs
- P.D.G. affects choice of statistics

**Notes:**
Despite not knowing, or lacking full knowledge of why Disparities exist; reduction in Inequalities must be pursued vigorously. 

The function of measuring Disparity may be in terms of a more passive way such as in Monitoring how different groups are, or actively as part of an Intervention program.  Realizing though, that implicit in Intervention is an ethical judgment of “How things should be”

Finally, the choice of statistics to measure Disparity depend on the philosophical approach (or purpose), Data type or demographic group, and goal.

## Handbook on Measuring Disparity

- Timeline – complete in 2002 ?
- Stakeholder engagement continues
- Handbook work group
- State, Federal, Academic
- Meetings
- NCVHS, DUC, HP Steering Committee, APHA

**Notes:**
We hope to have completed work on a handbook for measuring disparity by the end of this year.

In the meantime, we are continuing to refine its contents, through input from the handbook work group that includes members from State Health Departments, Universities, and various Federal Agencies.

In addition we are receiving valuable feedback through public meetings such as the National Committee on Vital and Health Statistics, Populations Subcommittee, This Data User’s Conference, The Healthy People 2010 Steering Committee, and the coming APHA conference in Philadelphia

Now, I’d like to shift from a discussion of some of the more abstract components of measuring disparity to more practical matters.