# Presentation: 448062

## Kenneth G. Keppel, PhD

**Kenneth G. Keppel, PhD**

**Centers for Disease Control and Prevention**
**National Center for Health Statistics**

## Slide 2

**Notes:**
targets and LHIs – notation on charts

2nd goal eliminate disparity.
A lot of racial detail – more than most
** just because a category is there doesn’t mean there aren’t issues

## Goal 2:To eliminate health disparities among segments of the population, including differences that occur by gender, race or ethnicity, education or income, disability, geographic location, or sexual orientation.

## We know how to measure the disparity between two race/origin groups.andWe know how to determine whether the disparity between two race/origin groups changed over time?

## Age-adjusted homicide death rates, 1990 and 2000

- <date/time>

- Source:  CDC, NCHS, National Vital Statistics System

- Per 100,000 population

- 8.4

- 			 **Absolute difference**	                     % change
- 	     **12.2**	               Deaths per 100,000 	          **5.6 **       **- 54 % **
** ****	****	****	****  ****Relative difference**
- 	    **305**** **  Percent difference(H-WnH)/WnH *100      **200 **          **- 34 %**
- 	         **4.05**              Ratio (H/WnH)	          **               3.0**        **- 34 %**

- White
-  not-Hispanic

**Age-adjusted homicide death rates, 1990 and 2000**

- White
-  not-Hispanic

- Hispanic

- Hispanic

- 2.8

- 16.2

- 4.0

- _1990_

- _2000_

## We also know how to compare the disparity between two race/origin groups in one indicator with the disparity between comparable groups in another indicator.

## Age-adjusted homicide rates, 2000

- <date/time>

- Source:  CDC, NCHS, National Vital Statistics System

- Per 100,000 population

- 8.4

**Age-adjusted homicide rates, 2000**

- 2.8

- Hispanic

**Age-adjusted suicide rates, 2000**

- 12.1

- 6.1

- Per 100,000 population

- White
- non-Hispanic

- Absolute difference        **5.6**
-  Percent difference     **200**
- (H-WnH)/WnH * 100
-              Ratio                      **3.0**
-            (H/WnH)
- Absolute difference       **6.0**
-  Percent difference     **- 50**
-  (H-WnH)/WnH *100
-               Ratio                      **0.5**
-             (H/WnH)

- Hispanic

- White
- non-Hispanic

## Goal 2:To eliminate health disparities among segments of the population, including differences that occur by gender, race or ethnicity, education or income, disability, geographic location, or sexual orientation.

## How is the disparity among race/origin groups changing over time?

## Age-adjusted homicide rates by race and Hispanic origin, 1990 and 2000

- Per 100,000 population

- Source:  CDC, NCHS, National Vital Statistics System

**% change**

- Log scale

## How does the disparity among race/origin groups in one indicator compare with the disparity among race/origin groups in another indicator?

## Age-adjusted homicide rates, 2000

- <date/time>

- Source:  CDC, NCHS, National Vital Statistics System

- Per 100,000 population

- 8.1

**Age-adjusted homicide rates, 2000**

- 8.4

- 12.1

- 6.1

**Age-adjusted suicide rates, 2000**

- Per 100,000 population

- 5.8

- 12.0

- 5.8

- 21.8

- 2.8

- 3.1

## Measures of Disparity

- Between two groups
- Simple difference
- Percent difference
- Ratio

- Among several groups
- Mean deviation
- Index of disparity
- Average of ratios

***Absolute ******      ***

***Relative***

## Measures of Disparity

- Between two groups
- Simple difference
-        ri – rrp
- Where ri is the rate for group i and rrp is the rate for the other group which is also the reference point.

- Among several groups
- Mean deviation
- ni=1ri – rrp
-         n
- Where ri is the rate for each group i, rrp is the rate for the reference point and n is the number of groups.

***Absolute ******      ***

## Measures of Disparity

- Between two groups
- Percent difference
-    ri – rrp / rrp * 100
- Where ri is the rate for group i and rrp is the rate for the other group which is also the reference point.

- Among several groups
- Index of disparity
- ni=1ri – rrp
- 	        n
- Where ri is the rate for each group i, rrp is the rate for the reference point and n is the number of groups.

- rrp * 100

***Relative***

## Measures of Disparity

- Between two groups
- Ratio
-    ri / rrp
- Where ri is the rate for group i and rrp is the rate for the other group which is also the reference point.

- Among several groups
- Average of ratios
-        [ni=1 |(ri / rrp) - 1|]
-               n
- Where ri is the rate for each group i, rrp is the rate for the reference point and n is the number of groups.

***Relative***

## Index of disparity

- 		     Race and origin        2000      ri – rrp
-             Native American, r1               8.1	  2.0
-     Asian/Pacific Islander, r2               3.1	  3.0
-                          Hispanic, r3               8.4	  2.3
-         Black non-Hispanic, r4            21.8	15.7
-         White non-Hispanic, r5           2.8	  3.3
** ****(Reference Point)** Total, rrp         6.1	    ---
-                     (ni=1ri – rrp/ n)   =   5.3
- 	  (ni=1ri – rrp/ n) / rrp * 100  =   86 %

- Age-adjusted
- homicide rate

## Age-adjusted homicide rates by race and Hispanic origin, 1990 and 2000

- Per 100,000 population

- Source:  CDC, NCHS, National Vital Statistics System

**95%                        86%     Index of disparity**

- Log scale

## Age-adjusted homicide rates, 2000

- <date/time>

- Source:  CDC, NCHS, National Vital Statistics System

- Per 100,000 population

- 8.1

**Age-adjusted homicide rates, 2000**

- 8.4

- 12.1

- 6.1

**Age-adjusted suicide rates, 2000**

- Per 100,000 population

- 5.8

- 12.0

- 5.8

- 21.8

- 2.8

- 3.1

**Index of disparity**
**86 %**
**32 %**

## The index of disparity is:

- A measure of the degree of disparity among several group rates
- A summary measure based on an average
- Dependent on choice of a reference group
- Suitable for categorical groups
- A relative statistic
- Easy to calculate
- Easy to interpret

## The index of disparity is NOT:

- A measure of improvement in group rates
- A basis for prioritizing disparities
- A substitute for individual group-specific rates

## Percent of low birthweight infants, 1990-2000

- Percent

- Source:  CDC, NCHS, National Vital Statistics System

- 28.4%   Index of disparity         23.2%

## The index of disparity could be used to determine whether the disparity among race/origin groups, or among education groups, or among income groups is getting smaller?