This document summarizes research using California Health Interview Survey (CHIS) data to examine cancer screening disparities among racial/ethnic groups in California. The research found that Hispanic and African American women were more likely than white women to report recent Pap tests, but Asian women were less likely. Pap test use varied among Hispanic and Asian subgroups. For example, Mexican women reported fewer Pap tests than Central and South Americans. The research also found that lack of U.S. citizenship was a barrier to cancer screening among immigrant women.

1. Using CHIS data to explore
Cancer screening disparities
in California
Israel De Alba, MD MPH
Center for Health Policy Research
Department of Medicine
University of California, Irvine

2. Overview
Using CHIS data to explore cancer screening
racial/ethnic disparities: two examples
1. Pap smear use in California: are closing the racial/ethnic
gap?
2. Impact of U.S. citizenship status on cancer screening
among immigrant women

4. Background
Cervical Cancer Screening in California
Nearly 14% of all new cases nationwide are
diagnosed in women residing in California
The cervical cancer age adjusted incidence
rate in the state is above the national average

5. Background
Cervical Cancer Screening in California
California has one of the largest
proportions of minority populations in
the country; one in every three state
inhabitants is of Hispanic origin and one
in nine of Asian descent

6. Background
Study Aims
Aim 1.
To assess the impact of race/ethnicity on Pap
smear use among women in California
Aim 2.
To examine the effect of ethnic sub-groups
on cervical cancer screening among Hispanic
and Asian women in California

7. Methods
Inclusion criteria:
1. Women age ≥18
2. No hysterectomy
Outcomes
1. Receipt of recent Pap smear
(in past 3 years)
1. Ever having a Pap smear

8. Methods
Statistical analysis
1. Descriptive statistics
2. Bivariable analysis
3. Logistic regression
4. Generation of prevalence rate ratios

9. Methods
Logistic regression models constructed
Population Dependent
variable
Main independent
variable
Model 1 All women Recent Pap
smear
Race/ethnicity
Model 2 All women Pap smear
ever
Race/ethnicity
Model 3 Hispanics
only
Recent Pap
smear
Hispanic sub-group
Model 4 Hispanics
only
Pap smear
ever
Hispanic sub-group
Model 5 Asians only Recent Pap
smear
Asian sub-group
Model 6 Asians only Pap smear
ever
Asian sub-group

10. Methods
Hispanic sub-groups
Mexican
Central American
South American
Other

11. Methods
Asian Sub-groups
Japanese
Filipino
Korean
Chinese
Vietnamese
South Asians
• (Bangladeshi, Indian, Pakistani, Sri Lankan,
and more than one of these nationalities)

12. Methods
Adjusting variables in logistic regression
Age
18-30, 31-40, 41-50 and ≥51
Educational attainment
< high school, high school, > high school
Annual household income
< 200% FPL or ≥ 200% FPL
Health insurance
any coverage or no insurance
Self-reported health status
excellent, very good or good vs. fair or poor
Ability to speak English (only among ethnic sub-groups)
very well, well, not well and not all

13. Results: all women
Demographics (N=25,228)
Age distribution 18-30 30%
31-40 25%
41-50 20%
≥51 25%
Race/ethnicity: White 50%
Hispanic 30%
Asian 11%
African American 5%
Other 4%

14. Results: all women
Pap smear use adjusted prevalence rates ratios
Recent Pap Pap ever
White 1.0 1.0
Hispanic 1.03* .99
Asian .81* .82*
African American 1.03* 1.01
Other .96 .98
* ≤ 0.05

15. Results: Hispanic subgroup analysis
Pap smear use adjusted prevalence rate ratios
Recent Pap Pap ever
Mexican 1.0 1.0
Central American 1.06* 1.04
South American 1.07 1.07
Other Hispanic 1.01 .99
* ≤ 0.05

16. Results: Asian subgroup analysis (N=2,625)
Pap smear use adjusted prevalence rate ratios
Recent Pap Pap Ever
Filipino 1.0 1.0
Korean 0.95 0.91
Japanese 0.95 0.84
Chinese 0.95 0.79*
Vietnamese 0.93* 0.78*
South Asian 0.93* 0.73*
* ≤ 0.05

17. Summary
In California, Hispanic and African American
women are significantly more likely to report
having a recent Pap smear as compared to
White women and they are as likely to report
a Pap smear ever
Asians, however, were significantly less likely
to report having a Pap smear recently or ever
despite a favorable sociodemographic profile

18. Summary
Pap smear use rate varied by ethnic
subgroup
Mexican women were less likely to report
recent or ever Pap smear as compared to
Central and South Americans

19. Summary
Among Asians:
• Filipino and Korean women are the most likely
to report recent or ever Pap smear
• South Asians, Chinese and Vietnamese were
least likely to report any of these outcomes

20. Having a usual source of care and income
contributes the most to Pap smear use
among all women and Asians in California
Health insurance and income are the most
important contributors to use of Pap smears
among Hispanics
Summary, other findings

21. Limitations
Self-report of receipt and timing of Pap smear
Low response rate for 2001 CHIS (63.7%)
Non-response bias
Generalizability

23. Specific aim
To evaluate the relationship between
U.S. citizenship status and receipt of
Pap smears and mammograms among
immigrant women in California.

24. Rationale
Non-U.S. citizen immigrants may be
disproportionately affected by access
and cultural barriers
California has a higher percentage of
non-U.S. citizens than any other state

25. Outcomes
Cervical cancer screening among immigrant
women age 18 or older without a hysterectomy:
• Pap smear in the past three years
• Pap smear ever
Breast cancer screening among immigrant women
age 40 or older:
3. Mammogram in the past two years
4. Mammogram ever

26. Statistical analysis
Multivariable logistic regression model for each
outcome
Adjusting for:
Age
Race/ethnicity
Educational attainment
Annual household income
Having health insurance
Years in the U.S.
Health status
English language proficiency

27. Results
6,320 women were included in our
analysis of cervical cancer screening;
47% were U.S. citizens
3,828 in the analysis of breast cancer
screening; 65% were U.S. citizens

28. Results

29. Results

30. Conclusions
Not being a U.S. citizen is a barrier to receiving
cervical and breast cancer screening
Additional research is needed to explore causal
factors for differences in cancer screening rates
between citizens and non-U.S. citizens
Immigrants, especially those who are not U.S.
citizens, should be targeted for improved health care
access and appropriate cancer screening.

31. Using CHIS data to explore cancer screening
racial/ethnic disparities: overall impressions
Positive aspects
Data easily available
Well designed, standardized
questionnaires
Excellent “customer service”
High proportion of minority populations

32. Using CHIS data to explore cancer screening
racial/ethnic disparities: overall impressions
Minor comments
Low response rate in 2001 CHIS
Limitations of a phone survey