Effects of Racial and Ethnic Aggregation on Birth Outcome by mwz19860

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									Effects of Racial and Ethnic Aggregation
   on Birth Outcome Measures for the
American Indian Population of California
              (2000-2002)


                   David Dodds, PhD, MPH
            Epidemiology and Evaluation Section
        Maternal, Child and Adolescent Health Branch
          California Department of Health Services
                       December, 2006
                     ddodds@dhs.ca.gov
         Background: American Indian
           Population and California
• California has the largest American Indian population among states:
     – 333,000 (race alone, Census 2000)
     – 628,000 (race alone or in combination, Census 2000)1

• California is home to:
     – 12 percent of the United States population
     – 13.5 percent of the American Indian/Alaska Native population2

• Los Angeles County has the largest American Indian population
  among United States counties.3

• California is home to 106 of 561 federally recognized tribes.4

• Most American Indians in California declare ancestry deriving from
  non-California tribes.5

*Sources: (1) Census 2000 Summary File 1, Table QT-P6; (2) State of California, Department of Finance, Census 2000:
Summary File 1 California Profile, Sacramento, California, 2002.; (3) Census 2000 PHC-T-14,Table 11; (4) Federal Register,
November 25, 2005, Vol. 70, No. 226: 71194-71198 ; (5) Census 2000 PHC-T-18, Table 19.
 Background: Births and Disparities
• California ranks third in number of American Indian births
  among states:
       – Rank 1: Oklahoma (≈ 5,000 per year)
       – Rank 2: New Mexico (≈ 3,500 per year)
       – Rank 3: California (≈ 3,000 per year)1

• Disparities persist for American Indians in California and
  the United States as measured by birth outcomes:
       – Infant mortality
       – Low birth weight
       – Pre-term delivery



Source: (1) Martin, JA, et al. (2003). Births: Final Data for 2002. National Vital Statistics Reports, Vol. 52, No. 10.
Hyattsville, Maryland: National Center for Health Statistics (Table 11).
Infant Mortality Rate, California and United States,
        2000-2002 Linked Files, by Race*

                                          16.0                                                    California
                                                                13.5                              U.S.
                                          14.0
                                                                                                  HP 2010 (4.5)
    Infant deaths per 1,000 live births




                                          12.0               11.4

                                          10.0                                8.9
                                                                        7.6
                                           8.0                                                       6.9
                                                       5.7                                     5.4
                                           6.0   5.0
                                                                                    4.5 4.8
                                           4.0

                                           2.0

                                           0.0
                                                 White        Black    American     Asian or    Total
                                                                        Indian       Pacific
                                                                                    Islander
*Race regardless of Hispanic ethnicity. Sources, California and United States: Matthews, TJ, et al. (2004).
Infant mortality statistics from the 2002 period linked birth/infant death data set. National Vital Statistics
Reports, Vol. 53, No. 10. Hyattsville, Maryland: National Center for Health Statistics (Table 3). Healthy People
2010, wonder.cdc.gov/data2010.
                                 Study Problem
 • Race and ethnicity are conventional categories for
   assessing health disparities in public health.

 • Current federal guidelines (OMB 1997) require separate
   categories of race and ethnicity for data collection.1

 • The federal race category “American Indian or Alaska
   Native” overlaps significantly with:
       – Other races (alone or in combination)
       – Hispanic ethnicity



Source: (1) Office of Management and Budget, 1997, Revisions to the Standards for the Classification of Federal Data on
Race and Ethnicity, Federal Register Notice, October 30, 1997, www.whitehouse.gov/omb/fedreg/1997standards.html.
            Study Questions
• Given overlap between races and ethnicity for
  American Indians, do different racial/ethnic
  aggregation techniques alter birth outcome
  measures?

• Are some racial/ethnic aggregation techniques
  more useful than others?
  California: Race and Ethnicity
• California has a large Hispanic population.

• Race/ethnicity data are often aggregated before
  analysis: Hispanics first into one group with remainder
  groups as non-Hispanic race groups.

• This technique can diminish statistical size of the
  American Indian population in states like California.
                         Example of “Hispanic First” Aggregation:
                             California Resident Live Births
                          by Maternal Race and Ethnicity, 2005
                                      (N=548,700)


                                                                                                          Hispanic: 51.5%

                                                                                                          White: 29.8%

                                                                                                          Asian: 11.3%

                                                                                                          African American: 5.2%

                                                                                                          Multiple Race: 1.3%

                                                                                                          Pacific Islander: 0.5%

                                                                                                          American Indian: 0.4%




All race groups are Non-Hispanic for White, Asian, African American, Multiple Race, Pacific Islander, American Indian. Data source: Birth
Statistical Master File, 2005, analysis by author.
                   Example Data:
    California Resident Births 2000-2002 Pooled,
           by Race and Ethnicity (Number)

                                                                NOT
RACE                                                        HISPANIC               HISPANIC               TOTAL

American Indian/Alaska Native                                       5,927                  1,541           7,468

Asian                                                           175,692                    1,402         177,094

Black                                                             93,070                   2,018          95,088

Two or more                                                       19,454                 10,133           29,587

Native Hawaiian or Pacific Islander                                 7,143                     234          7,377

Unknown                                                           10,696                      258         10,954

White/Other                                                     494,077                766,457          1,260,534

TOTAL                                                           806,059                782,043          1,588,102

              Source: Linked birth and death cohort files, California, 2000-2002, analysis by author.
                         Example Data:
          California Resident Births 2000-2002 Pooled,
                 by Race and Ethnicity (Percent)


RACE                                                     NOT HISPANIC                      HISPANIC          TOTAL

American Indian/Alaska Native                                              0.37                      0.10      0.47

Asian                                                                     11.06                      0.09     11.15

Black                                                                      5.86                      0.13      5.99

Two or more                                                                1.22                      0.64      1.86

Native Hawaiian or Pacific Islander                                        0.45                      0.01      0.46

Unknown                                                                    0.67                      0.02      0.69

White/Other                                                               31.11                    48.26      79.37

TOTAL                                                                    50.76                     49.24     100.00

                   Source: Linked birth and death cohort files, California, 2000-2002, analysis by author.
          Study Problem (continued)
• Among federally defined race groups in
  California, overlap with Hispanic ethnicity was
  highest for American Indians in Census 2000:
      – 46% of Californians who chose American Indian race
        alone indicated Hispanic ethnicity.1
      – 39% of Californians who chose American Indian as
        race alone or in combination with another race,
        indicated Hispanic ethnicity.2



Source: American Fact Finder, factfinder.census.gov: (1) Census 2000 Summary File 1 (SF 1), P8. Hispanic or Latino
by Race [17] - Universe: Total population; (2) Census 2000 Summary File 1 (SF 1), P10. Hispanic or Latino by Race
(Total Races Tallied) [15] - Universe: Total races tallied.
    Study Problem (continued)
• For California births, there are somewhat similar
  overlaps in race and ethnicity.

• California linked files for births and deaths
  during 2000-2002 show that:
   – 21% of births by American Indian race alone overlap
     with Hispanic ethnicity.1
   – 34% of births by American Indian race alone or
     combination overlap with Hispanic ethnicity.1


     Source: Linked birth and death cohort files, California, 2000-2002, analysis by author.
                             Methods
• Test three aggregation techniques for American Indians:
    – Technique 1: American Indian race alone, Not Hispanic
    – Technique 2: American Indian race alone
    – Technique 3: American Indian race alone or in combination

• Assess effects of aggregation technique on three birth outcome
  measures:
    – Infant mortality
    – Percent of births with low birth weight
    – Percent of pre-term births

• Data: Cohort files of linked California birth and death certificates for
  pooled years 2000-2002. Three years of data:
    – Improves rate stability assessed by relative standard error (RSE)
    – Allows for comparison of state and national data as published by the
      National Center for Health Statistics
  Birth Outcome Measures with 95% Confidence Intervals:
        Three Aggregation Techniques for American
  Indians/Alaska Natives Resident to California, 2000-2002
Aggregation                         Infant Mortality                  Low Birth Weight                     Pre-Term
Technique                           (infant deaths                    (percent < 2500                      Delivery
                                    per 1,000 live                    grams)                               (percent < 37
                                    births)                                                                wks gestation)
1) American
Indian race alone,                            8.3                                6.1                              12.4
Not Hispanic1                             (5.9, 10.6)                         (5.5, 6.8)                      (11.4, 13.4)
2) American
Indian race                                   7.5                                6.0                              12.4
alone2                                     (5.5, 9.5)                         (5.5, 6.6)                      (11.4, 13.2)
3) American
Indian race alone                             7.5                                6.9                              12.3
or combination3                            (6.2, 8.8)                         (6.5, 7.3)                      ( 11.7,12.8)
Birth cohort denominators, 2000-2002 pooled: 1) Infant Mortality N=5,927; LBW N=5,926, PTD N=5,365. 2) Infant Mortality N=7,468; LBW
N=7,467; PTD N=6,769. 3) Infant Mortality N=17,172; LBW N=17,172; PTD N=15,825. Data filters: LBW, birthweight 227 to 8650 grams; PTD,
gestational age 17 to 47 weeks.
                                  Birth Outcome Measures by
                       Aggregation Technique for American Indians/Alaska
                           Natives Resident to California, 2000-2002

                      16.0
                                        Race Alone, Not Hispanic
                      14.0              Race Alone
                                                                                      12.4   12.3   12.3
                      12.0              Race Alone or in Combination
    Rate or Percent




                      10.0
                                  8.3
                       8.0               7.5    7.5
                                                                           6.9
                                                              6.1    6.0
                       6.0

                       4.0

                       2.0

                       0.0
                               Infant Mortality (Infant     Low Birth Weight (% )   Pre-Term Delivery (% )
                             deaths per 1000 live births)

Source: Linked birth and death cohort files, California, 2000-2002, analysis by author.
                         Results
• Alternative aggregation techniques can change
  descriptive birth outcome measures.

• As aggregations use less restrictive criteria:
   – denominators increase in size
   – confidence intervals narrow in width
   – outcome measures (rates, percents) vary

• However, the three techniques tested do not produce
  measures significantly different from each other.
  Confidence intervals (95%) overlap across techniques
  for each birth outcome measure.
                         Conclusions
•   Technique 1: “American Indian Race Alone, Not Hispanic”
     – Advantages: Captures important demographic trends in California
       related to growth of the Hispanic population by immigration and high
       fertility. Exclusive categories are easy to understand: all numbers sum
       to 100%.
     – Disadvantage: Possibly too restrictive for assessing health needs of the
       California American Indian population since “race alone” population may
       be moved to Hispanic
•   Technique 2: “American Indian Race Alone”
     – Advantages: Captures the racial heterogeneity of people with American
       Indian ancestry. Avoids “loss to Hispanics.” Exclusive categories are
       easy to understand: all numbers sum to 100%.
     – Disadvantage: Loss of Hispanic category misses large scale
       demographic trend.
•   Technique 3: “American Indian Race Alone or in Combination”
     – Advantage: Captures the most racial heterogeneity (i.e., racial overlap)
       of people with American Indian ancestry.
     – Disadvantage: Inclusive categories may be confusing because they
       sum to more than 100% of the population.
     Public Health Implications
• Different racial/ethnic aggregation techniques can
  provide alternative perspectives for assessing health
  disparities for heterogeneous populations like American
  Indians of California.

• However, in the case of birth outcome measures for
  California the techniques tested did not provide
  significantly different measures. Other measures and
  other states may be different.

• Each technique has its own advantages and
  disadvantages.
      Public Health Implications
• Choice of a useful racial/ethnic aggregation technique
  must address purposes of data use.

• Choice of aggregation technique involves trade-offs
  among criteria such as:
   – Ability to identify a population for a target purpose (e.g., health
     services access or detecting a particular disparity)
   – Ability to compare birth outcomes measures in published
     literature
   – Ease of interpretation by the public

								
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