7th National Changing Patterns of Cancer in Native Communities:
The Power of Partnerships:
American Indians and Alaska Natives:
The California Health Interview Survey Data
Findings and How to Use CHIS
September, 2007
Delight E. Satter, M.P.H. (Confederated Tribes of Grand Ronde)
Director, American Indian and Alaska Native Research Program
UCLA Center for Health Policy Research
Presentation Objectives
 Report cancer specific data findings from several studies conducted by AIANRP.
 Provide overview information on accessing the CHIS data, available to the
public.
 Lastly, it will provide step-by-step instructions with examples on using AskCHIS,
the CHIS on-line data query system. This section of the presentation will be
interactive, live, and web-based. The audience will determine the data requests
we run together. Examples of data queries the audience might request are:
 Estimating breast cancer screening rates for urban California Native women aged
40+ and pooling CHIS 2001, 2003 and 2005 data.
 Comparing cervical cancer screening rates for urban versus rural Native women
across time.
 Estimating tobacco use rates for Native adults residing in Northern California
versus Southern California.
 Comparing obesity rates for male versus female Natives by age groups (e.g. 1844, 45 – 64, 65+).
 Identifying differences in access to Indian Health Service by tribal affiliation.
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American Indians and Alaska Natives in California Background
 More AIAN reside in CA than any other single state in the US.
California is home to AIAN from 107 federally recognized tribes.
AIAN residing in CA are extremely diverse with most being members
from reservations outside the state as compared to those who are
members from reservations inside the state.
 The majority of AIAN in CA live in urban areas, with Los Angeles
being home to the largest urban population of AIAN in the country.
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What is CHIS?
 A unique resource for California
 A public-private sponsored collaborative research project of:



UCLA Center for Health Policy Research
California Dept. of Health Services
Public Health Institute
 Provides comprehensive information about the health of Californians



Over time
By geographic area (county)
By population group/s
 Race/ethnic
 Poverty level
 Age
 Etc.
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What is CHIS?
 A population-based telephone health survey
 Three separate interviews



Adults (age 18+)
Adolescents (age 12-17)
Children (age 0 to 11)
 Widely disseminated



Publications
Public Use Files (PUFs)
AskCHIS Internet query system
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How is CHIS done?
 Conducted every other year since 2001
 Statewide random digit dial telephone survey


Sufficient adult interviews in each of 41 counties to provide
statistically stable estimates
Oversamples of Koreans & Vietnamese (and AIAN in 2001)
 One adult selected at random in each household; children and teens
as appropriate
 Conducted in English, Spanish, Chinese (Cantonese and Mandarin),
Korean, and Vietnamese
 Through a sub-contract with Westat, Inc.

Nearly 2 million phone calls made in CHIS 2005
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New for CHIS 2007
 Cell phone only sample – to address this growing population

Cell phone numbers are not included in RDD sample frames

Method pilot tested in 2005

CHIS 2007: expand to a statewide sample of 800-1,000 and include
in adult data files
 Area probability sample – to address declining response rates

Area probability sample in Los Angeles County (sample of
addresses rather than phone numbers)

Telephone and in-person recruitment

Compare estimates from RDD and area probability frames to
explore non-response bias
7
CHIS sample design
 Change in geographic stratification
 Increased total number of strata from 41 to 44
 Increased individual county strata from 33 to 41
 New—Monterey, Humboldt, Nevada, Mendocino, Lake, Yuba, Sutter, San
Benito
 Reduced multi-county strata from 8 (with 25 counties)
to 3 (with 17 counties)
 Tehama-Glenn-Colusa
 Sierra balance (Tuolumne, Calaveras, Amador, Inyo, Mariposa, Mono, Alpine)
 New—Northern balance (Siskiyou, Del Norte, Lassen, Trinity, Modoc,
Plumas, Sierra)
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What information does CHIS collect?
 Rich demographic data, including:




Age, sex, race/ethnicity, marital status
Country of birth, years in US, citizenship, mother/father’s country of
birth, language/s spoken at home, English proficiency
Employment status, income, poverty level, educational attainment
AIAN specific data: tribal affiliation(s), enrolled in state or federally
recognized tribe, where enrolled
 Health behaviors, including:



Alcohol and tobacco, illicit drugs (teens) use
Physical activity, dietary intake, environmental
Cancer screening, flu shot, HIV/STD testing, use of seat belts and
bike helmets
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What information does CHIS collect?
 Health conditions:




General health
Chronic conditions such as asthma, diabetes, heart disease, high
blood pressure, COPD, etc.
Disability
Mental health
 Access to and use of health care services



Usual source of care
Visits to doctor, ER use
Communication with doctor, need for translator, health literacy
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What information does CHIS collect?
 Health insurance coverage:





Current coverage
Coverage type (employer-based, private purchase, MediCal,
MediCare, Healthy Families)
HMO enrollment and plan details
Coverage past 12 months
Employer
 Uninsured


Reasons for lack of coverage
MediCal and Healthy Families eligibility (age < 65)
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What information does CHIS collect?
 Other topics & information






Food security and hunger
Public program participation

… and numerous other topics
Geocoding of households and schools
Social relationships and neighborhood conditions (2003)
Family history of cancer (2001, 2005)
Inter-personal violence (2007)
12
How to Get CHIS Data
How to get CHIS data?
 Public Use Files
 Source Files at the Data Access Center
 AskCHIS Internet query system
 Publications on the Center’s webpage www.healthpolicy.ucla.edu
 In journal articles
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CHIS Public Use Files (PUFs)
The CHIS Public Use Files are . . .
 Publicly available for free from the CHIS website
 Available separately for Adults, Children, and Adolescents
 Available for 2001, 2003, and 2005
 Microdata files – each record in the file is an individual case
(i.e., a completed interview)
 Available in SAS, STATA, and SPSS format
15
CHIS Public Use Files (PUFs)
The CHIS Public Use Files . . .
 Include detailed demographic information, but do not include
geographic identifiers or other sensitive variables that could
disclose respondent identity
 Include imputed values for missing data for most variables
 Include sample weights
16
What are weights & How are they constructed?
 Weights are variables that can be applied to the data to produce
population estimates
 There are separate weight variables for the adult, child, and
adolescent files
 The weights are constructed through a complex and iterative
process
 First, a base weight is calculated for each telephone number
based on the probability of selection at the stratum level
(county or group of small counties) and adjusted to produce
a final household weight
17
What are weights & How are they constructed?
 The adult, child, and adolescent weights are produced in a
similar fashion from the final household weight
 The adult weight is adjusted based on the number of adults in
the household and then “raked” in an iterative process to
control for several demographic and socio-economic
characteristics
 The weights are raked to population totals at the county level
based on California Department of Finance (DOF) population
projections
 The weights for each CHIS file (Adult, Child, and Adolescent)
sum to the total California population living in households as
projected by DOF
18
An example of unweighted and
weighted estimates
Has a doctor ever told you that you had a cancer of any kind?
Unweighted
Weighted
N
Percent
N
Percent
YES
4,272
11.2
2,127,075
8.3
NO
37,717
88.8
23,469,986
91.7
Total
42,044
100.0
25,597,061
100.0
Source: CHIS 2003 Adult Public Use File
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How to use the weights?
 The weight variables are included in the Public Use Files
 The weight variable name is RAKEDW0 in the Adult, Child,
and Adolescent files
 Weights are applied differently in different software packages
 Detailed instructions on how to apply the weights in SAS,
SPSS, and STATA are available on the CHIS web site
20
What are replicate weights?
 In addition to the full sample weight (RAKEDW0), there are 80
additional “replicate weights” (RAKEDW1 through RAKEDW80)
 Replicate weights are used to account for the geographically
stratified CHIS sample design
 The replicate weights allow accurate standard errors to be
calculated (the estimates do not change), without revealing
respondent geography
 The replicate weights are used with software packages such as
SUDAAN and WesVar
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CHIS confidential data
 Confidential CHIS data is available to researchers through the
UCLA Center for Health Policy Research Data Access Center
(DAC) – contact Brandan Troudt (btraudt@ucla.edu)
 DAC applications and additional DAC information are available
online at www.chis.ucla.edu
 Confidential data can be accessed in person at the DAC or
remotely through emailed programming code and results by
contracting with the Center’s Statistical Support and
Programming team (submit programming, or hire programmer)
22
Technical Assistance
 Additional documentation on CHIS survey methods, use of weights,
data dictionaries, and the questionnaires are available on the CHIS
web site at www.chis.ucla.edu
 Technical assistance on the Public Use Files is available at:
 Email: chis@ucla.edu
 Telephone: 866-275-2447 - Brandon Traudt
 Technical assistance on developing research question specific
to Native studies: Delight Satter – delight@ucla.edu
23
CHIS total sample sizes
2001
2003
2005
Adult (18+)
56,270
42,044
43,020
Child (0-11)
12,802
8,526
11,358
Teen (12-17)
5,733
4,010
4,029
24
Source: A Pleasant, but Puzzling Surprise: Twice as Many AIAN Are Found in a Large Health Survey in California,
AHSR, 2002, Yen and Satter
Table 2. Expected and Actual Sample Yields by Race, CHIS 2001
African
White
American
AIAN
Unadjusted Census Percent
67.6%
6.9%
0.9%
Expected Yield
70.4%
5.9%
1.1%
Actual Yield
69.9%
4.7%
1.7%
Asian
9.6%
8.1%
7.1%
Other
Race
15.0%
14.5%
16.6%
Source: 2001 California Health Interview Survey
5
25
Racial/Ethnic data collection
and reporting
Race by
Ethnicity
American
Indian,
Alaska
Native
Native
Hawaiian,
Pacific
Islander
Asian, Asian African
American
American
White
Latino
Non-Latino
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Adult sample size by race/ethnicity - Single Race definition only
2001
2003
2005
9,460
7,135
6,369
Native Hawaiian Pac Islndr
219
152
120
Am Indian Alaska Natives
781
580
554
Asian
4,798
3,875
3,941
African American
2,764
2,691
1,954
White
36,729
26,506
28,979
Latino
27
Data collection results
Graph 1. CHIS AIAN Sample Yields by Questions Percent of All RDD Known Race (52,451)
3000
2694
2138
2000
1000
0
332
311
Any mention of
AIAN
Named tribal
heritage
Enrolled Member
Named the
Enrolled Tribe
N
2694
2138
332
311
Percent
5.1%
4.1%
0.6%
0.6%
Includes persons interviewed in RDD survey and some county oversamples; it does not include listed oversamples.
These sample sizes are preliminary and may change depending upon further data cleaning and processing.
28
Adult, teen & child sample size by - American Indian or Alaska Native
one or more races definition
2003
2005
Adult
1897
1845
Teen
313
365
Child
463
370
29
Cancer Data published by AIANRP
 www.healthpolicy.ucla.edu
 Click on American Indian Research Program
 Click on Publications
30
How to use AskCHIS
31
How to get CHIS data and information on the health of
Natives from www.healthpolicy.ucla.edu
Run your own customized search using AskCHIS - Instantly get state and
local data on hundreds of health topics
Review publications and data reports
Learn about current research
Find out upcoming training workshop on AskCHIS
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Great Data –what about my community outside California?
Use indirect estimates approach:
Rates x Population size in your community (by different age
groups) = estimated # with disease/illness in your community.
(Call a researcher or your local county epidemiologist for help –
that’s why we’re here. Download worksheet from Center’s
HealthDATA training materials online.)
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34
35
36
37
Who are those people who report more 2+ races?
38
39
Felt Downhearted, sad, blue (from SF12) by gender, AIAN
40
Did see a health professional for mental/emotional problems by Access to IHS
41
Binge Drinking past month, AIAN, CA
Source: 2005 California Health Interview Survey, Race - Census 2000
* = statistically unstable
Adol. (12-17)
Adult (18-64)
Senior (65+)
All Ages
%
95% C.I.
%
95% C.I.
%
95% C.I.
%
95% C.I.
7.2*
(1.4 - 13.0)
24.9
(20.1 - 29.8)
6.4*
(0 - 13.1)
19.9
(16.0 - 23.7)
Binge
drinking
42
Binge drinking, past month, AIAN, CA
43
Tested for HIV by Sexual Orientation, AIAN, 2005
44
Current Smoking status by Gender, 21 years old +, Any mention AIAN
45
Disability status by Gender, AIAN any-mention, CA
46
Physical Activity by CA Region, AIAN adults
47
Heart Disease (CVD) by Diabetes, AIAN adults
48
Live Interactive Session
49
For the Health of All Generations
UCLA Center for Health Policy
Research
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Contact Information
Delight Satter, M.P.H.
Director, American Indian and Alaska Native Research Program
UCLA Center for Health Policy Research
delight@ucla.edu
310 794 2686