2523 A Population-Based Study of Colorectal Cancer Test Use Results from the 2001 California Health Interview Survey David A. Etzioni, M.D., M.S.H.S. 1,2 Ninez A. Ponce, Ph.D., M.P.P. 3 Susan H. Babey, Ph.D. 3 Benjamin A. Spencer, M.D., M.P.H. 2,4 E. Richard Brown, Ph.D. 3 Clifford Y. Ko, M.D., M.S., M.S.H.S. 1,4,5 Neetu Chawla, M.P.H. 3 Nancy Breen, Ph.D. 6 Carrie N. Klabunde, Ph.D. 6 1 Department of Surgery, David Geffen School of Medicine at the University of California at Los Angeles, Los Angeles, California. 2 Robert Wood Johnson Clinical Scholars Program, University of California at Los Angeles, Los Angeles, California. 3 Department of Health Services, University of California at Los Angeles Center for Health Policy Research and the University of California at Los Angeles School of Public Health, Los Angeles, California. 4 Veterans Administration of Greater Los Angeles Healthcare System and the Department of Medicine, Los Angeles, California. 5 RAND, Santa Monica, California. 6 Health Services and Economics Branch, Applied Research Program, National Cancer Institute, Bethesda, Maryland. Supported in part by contract N02PC95057 from the National Cancer Institute and the Centers for Disease Control and Prevention and by grant 20002098 from The California Endowment. The authors greatly appreciate the support of Marion Standish, Program Director at The California Endowment; Dr. Ralph Coates, Associate Director for Science, Division of Cancer Prevention and Control, Centers for Disease Control and Prevention; and Dr. Rachel Ballard-Barbash, Associate Director, Applied Research Program, National Cancer Institute. Address for reprints: Ninez A. Ponce, Ph.D., M.P.P., University of California at Los Angeles Center for Health Policy Research, 10911 Weyburn Avenue, Suite 300, Los Angeles, CA 90024; Fax: (310) 794-2686; E-mail: nponce@ucla.edu Received April 12, 2004; revision received August 21, 2004; accepted August 25, 2004. BACKGROUND. Recent research has supported the use of colorectal cancer (CRC) tests to reduce disease incidence, morbidity, and mortality. A new health survey has provided an opportunity to examine the use of these tests in California s ethnically diverse population. The authors used the 2001 California Health Interview Survey (CHIS 2001) to evaluate 1) rates of CRC test use, 2) predictors of the receipt of tests, and 3) reasons for nonuse of CRC tests. METHODS. The CHIS 2001 is a random-digit dial telephone survey that was conducted in California. Responses were analyzed from 22,343 adults age 50 years. CRC test use was defined as receipt of a fecal occult blood test in the past year and/or receipt of an endoscopic examination in the past 5 years. RESULTS. Nearly 54% of California adults reported receipt of a recent CRC test. Insurance coverage and having a usual source of care were the most important predictors of CRC testing. Latinos age 65 years were less likely to be tested than whites (relative risk [RR], 0.84; 95% confidence interval [95% CI], 0.77 0.92). Men were more likely to be tested than women, an effect that was greater among individuals age 50 64 years (RR, 1.28; 95% CI, 1.23 1.32) than among individuals age 65 years (RR, 1.19; 95% CI, 1.15 1.23). Women were more likely than men to say that their physician did not inform them the test was needed and that CRC tests were painful or embarrassing. CONCLUSIONS. Results of the current study indicate a need for physicians to recommend CRC testing to their patients. Assuring that all individuals have both health insurance and a usual source of care would help address gaps in the receipt of CRC tests. Cancer 2004;101:2523 32. 2004 American Cancer Society. KEYWORDS: colorectal neoplasms, prevention and control, mass screening, ethnic groups, statistics and numeric data, endoscopy, utilization, occult blood, California. Colorectal cancer (CRC) is the third most common cancer both in California and nationally. In California, there were approximately 7400 new diagnoses of CRC and 2600 deaths from CRC in 2001. 1 Patient outcomes are highly dependent on the stage of disease at the time of diagnosis and surgery. When CRC is detected early, there is a reported 90% 5-year survival rate; among patients with advanced disease, the 5-year survival rate is reduced to 9%. 2 CRC screening is recommended by the American Cancer Society, the Centers for Disease Control and Prevention, the National Cancer Institute, and the U.S. Preventive Services Task Force. The specific guidelines proposed by each organization differ, but all recommend regular fecal occult blood testing (FOBT) and flexible sigmoidoscopy to reduce the disease burden of CRC for individuals age 50 years. 3 6 Despite the demonstrated benefits of CRC screening, the proportion of the population that receives CRC examinations remains quite low. In the 2000 National Health Interview Survey (NHIS), only 41% of 2004 American Cancer Society DOI 10.1002/cncr.20692 Published online 25 October 2004 in Wiley InterScience (www.interscience.wiley.com).
2524 CANCER December 1, 2004 / Volume 101 / Number 11 men and 38% of women were screened recently. 7 Past studies suggest that there are significant barriers to the widespread uptake of CRC screening and that these barriers may be more pronounced among minorities, females, individuals with low income, older adults, and rural residents. 8 14 Using data from the NHIS, researchers consistently have found CRC test use differences according to race, education, insurance status, and whether an individual has a usual source of care (USOC). 3,7,11 California is the most populous state in the U.S., and the 2001 California Health Interview Survey (CHIS 2001) is the largest state population-based health survey in the nation. The 1999 Behavior Risk Factor Surveillance Survey had approximately 1500 responses from California, and the 2000 NHIS surveyed 39,000 households nationwide. 7,15 The CHIS 2001, which is much larger, includes data from 55,000 households, with a sample design that has national significance. It informs policy at the national level, because it provides the only available data regarding several racial and ethnic groups with insufficient samples in national surveys, such as American Indians/Alaska Natives, Pacific Islanders, and Asians. In addition, the CHIS 2001 was administered in several other languages, resulting in the participation of populations that have been excluded historically from English-only administered population-based surveys. 16 Inclusion of these racial, ethnic, and linguistic minorities is particularly important in accurately evaluating the nation s progress in cancer screening. For the current study, we examined individual-level predictors of CRC test use and analyzed the reasons identified by different gender, racial, and ethnic groups for not undergoing CRC tests. Together, these analyses contribute to the CRC screening literature by identifying the groups most at risk for not receiving CRC screening tests and by providing insights into the reasons for varying screening rates. MATERIALS AND METHODS CHIS 2001 The CHIS 2001 sample and questionnaire were designed to represent California s ethnically diverse population: 55,428 households were selected randomly from within the state for a random-digit dial telephone survey. From each participating household, one randomly selected adult was interviewed. Respondents age 50 years were asked about their use of CRC tests. Data from the survey were weighted to the 2000 Census at the county and state levels. The completed interview participation rate was 63.7%. More detailed descriptions about the methods have been published elsewhere. 17 20 CHIS was approved by the University of California at Los Angeles Institutional Review Board and by the California State Committee for the Protection of Human Subjects. Inclusion Criteria Individuals age 50 years without a personal history of CRC were included in this study. Respondents for whom receipt of a colorectal test could not be determined as a result of having responded refused or don t know to questions concerning testing were excluded from all analyses. Dependent Variable: Receipt of Testing Survey respondents were considered tested if an FOBT was performed in the 12 months prior to the interview or if either a flexible sigmoidoscopy or colonoscopy was performed within 5 years prior to the interview. These frequency criteria parallel those used in analyses of NHIS data. 3 6 For the purposes of this analysis, we made no distinction regarding the reason an individual underwent testing. Classically, screening refers to the use of a test in an individual without symptoms. To avoid potential misclassification, the receipt of colorectal examinations for any reason was used as the outcome of interest and is reported as testing instead of screening. Variables We examined the extent to which demographic factors, socioeconomic status (SES), health insurance coverage, access to care, health status, and acculturation factors predicted CRC test use in a population of adults age 50 years. Many studies have shown that demographic characteristics (such as age, gender, and race/ethnicity) and indicators of SES are associated with the use of health care services. 21 24 Measures of access to care, health insurance coverage, and the presence of a USOC also are especially strong predictors of the receipt of preventive health care, such as cancer screening. 3,7,24,25 Finally, because of California s large immigrant population, we examined factors of acculturation. Studies have suggested that, among immigrants, English proficiency and recency of immigration to the U.S. are important factors in CRC screening. 7,26 Demographic variables Age was modeled as a continuous variable. Race and ethnicity were tabulated into six mutually exclusive categories (white, Latino, Asian, African American, other/multiracial, and American Indian/Alaskan Native). Marital status was analyzed as currently married, never married, or other.
Colorectal Cancer Test Use/Etzioni et al. 2525 SES and access-to-care indicators The socioeconomic variables examined included education and income. Education was grouped into four levels based on the highest level of education attained by the respondent (less than high school graduation, high school graduation, some college, and college degree or greater). Income was categorized based on the federal poverty level (FPL). The categories were FPL, 100 199% of FPL, 200 299% of FPL, and 300% of FPL. Access to care was constructed as a composite variable combining insurance status with the presence (or absence) of a USOC. Different variables were constructed for individuals age 65 years versus individuals age 65 years. For respondents age 65 years, insurance categories included employer-based, privately purchased, Medicaid/other public, or uninsured. For respondents age 65 years, insurance categories included Medicare and other, Medicare and Medicaid, Medicare only, no insurance (uninsured), or other only. Respondents were considered to have a USOC if they had a regular provider of care that was not an emergency department or an urgent care clinic. Health status and utilization Self-rated health status was included as a dichotomous variable (fair/poor vs. good/very good/excellent). The number of physician visits in the 12 months prior to the interview was categorized as 0 visits, 1 2 visits, 3 4 visits, 5 9 visits, or 10 visits. Acculturation Two variables were employed as indicators of acculturation. English proficiency was evaluated as a dichotomous variable (proficient in English vs. limited English proficiency). The percent of life years lived in the U.S. was constructed as a categoric variable based on the number of years lived in the U.S. and the respondent age. 26 Respondents were grouped into 3 categories (100% of life lived in the U.S., 0 50% of life lived in the U.S., and 51 99% of life lived in the U.S.). Reasons for Nonparticipation in Testing Respondents who reported that they did not undergo testing were asked the main reason for nonparticipation. One reason was obtained for each test modality. Frequencies of each reason for nonparticipation were compared for differences between gender and racial and ethnic groups using chi-square analysis. Racial/ ethnic differences were based on comparisons between each group and the reference group (white). Reasons for nonparticipation in FOBT and endoscopic testing were compared separately, because respondents could indicate a different reason for each modality. Statistical Analysis Weighted multivariate logistic regression was used to analyze each respondent s likelihood of undergoing CRC testing. Two regression models were estimated, 1 for respondents ages 50 64 years and 1 for respondents age 65 years, to account for age-related differences in health insurance coverage. For example, most adults age 65 years are covered by employerbased health insurance, and most adults age 65 years are covered by Medicare. Data analyses were performed with the Survey Data Analysis statistical package and SAS statistical software (version 8.01; SAS Institute, Cary, NC). Because the outcome was relatively common ( 10%), estimated relative risks (RR) and 95% confidence intervals (95% CI) were calculated using the adjusted odds ratios from the logistic regression models. 27 RESULTS Table 1 presents the characteristics of the 22,343 respondents who met the inclusion criteria. Of these, 12,211 respondents (55%) were ages 50 64 years, and 10,132 respondents (45%) were age 65 years. Women comprised 59.9% of the sample. The majority of respondents were white (80%); and the remainder of the sample consisted of Latinos (6%), Asians (5%), African Americans (5%), other/multiracial (3%), and American Indians/Alaska Natives (2%). Greater than half of respondents (55%) reported an income 300% of the FPL, 33% of respondents had attained at least a college degree, and 3% of respondents reported limited English proficiency. Unadjusted Rates of Test Use Nearly 54% of respondents in the sample reported receipt of a recent test for CRC. Table 2 presents unadjusted testing rates according to our independent variables for adult respondents age 50 64 years and age 65 years. Older adults were more likely to receive testing than younger adults; 62% of respondents age 65 years had a recent test, compared with 48% of respondents ages 50 64 years. In both age groups, men were more likely to have received a test than women. For both age groups, white and African-American individuals were more likely to be tested than individuals from other racial and ethnic groups. Among younger adults, 51% of whites and 50% of African Americans reported recent CRC testing; among older adults, the rates were 63% for whites and 62% for African Americans. Asians and Latinos had the lowest
2526 CANCER December 1, 2004 / Volume 101 / Number 11 TABLE 1 Sample s, California 2001 a,b TABLE 1 Unweighted no. (unweighted %) Unweighted no. (unweighted %) Age 50 64 yrs 12,211 (54.7) 65 yrs 10,132 (45.3) Gender Female 13,394 (59.9) Male 8949 (40.1) Race White 17,971 (80.4) Latino 1420 (6.4) Asian 1005 (4.5) African American 1042 (4.7) Other/multiracial 572 (2.6) American Indians/Alaska Natives 333 (1.5) Marital status Married 11,525 (51.6) Never married 1234 (5.5) Other (divorced, separated, widowed) 9584 (42.9) Income 300% FPL 12,194 (54.6) 200 299% FPL 3493 (15.6) 100 199% FPL 4558 (20.4) 0 99% FPL 2098 (9.4) Education College degree 7411 (33.2) Some college 6623 (29.6) High school 5787 (25.9) High school 2522 (11.3) Self-reported health status Good/very good/excellent 17,308 (77.5) Fair/poor 5035 (22.5) Insurance status Respondents ages 50 64 yrs Uninsured 414 (3.4) Medicaid or other public insurance 76 (0.6) Privately purchased 100 (0.8) Employer-based 367 (3.0) Uninsured 837 (6.9) Medicaid or other public insurance 1473 (12.1) Privately purchased 1071 (8.8) Employer-based 7873 (64.5) Respondents age 65 yrs Uninsured 13 (0.1) Other 15 (0.2) Medicare 78 (0.8) Medicare and Medicaid 73 (0.7) Medicare and other 185 (1.8) Uninsured 23 (0.2) Other 363 (3.6) Medicare 637 (6.3) Medicare and Medicaid 1604 (15.8) Medicare and other 7141 (70.5) No. of visits to physician in last 12 mos None 2171 (9.7) 1 2 7796 (34.9) 3 4 5489 (24.6) 5 9 3901 (17.4) 10 2986 (13.4) Percent of life lived in the U.S. 100% 19,527 (87.4) 51 99% 1604 (7.2) 0 50% 1212 (5.4) English proficiency Limited English proficiency 767 (3.4) No stated limits 21,576 (96.6) FPL: Federal poverty level; USOC: usual source of care. a Data were obtained from the 2001 California Health Interview Survey. b The sample included respondents age 50 years with no personal history of colorectal cancer. screening rates. Only 33% of younger Latinos and 52% of older Latinos had undergone a recent examination. Among Asians, only 42% of the younger group and 55% of the older group had undergone a recent test. Adults ages 50 64 years consistently were more likely to have been tested regardless of their health insurance status if they reported having a USOC. Among respondents with employer-based health insurance coverage, 53% of individuals with a USOC underwent testing, compared with 23% of individuals with no USOC. Lack of insurance combined with no USOC led to dramatically poorer rates of test use. Only 8% of uninsured individuals with no USOC reported a recent test. Most older adults age 65 years were covered by Medicare plus supplemental insurance (71%). Within this insurance group, having a USOC was associated with higher rates of screening (31% for respondents with no USOC compared with 66% for respondents with a USOC). Multivariate Results Table 3 presents the results of our multivariate models for predicting receipt of CRC screening for adults ages 50 64 years and age 65 years. Men in both age groups were more likely to be tested than women. This effect was greater in respondents ages 50 64 years (RR, 1.28; 95% CI, 1.23 1.32) than in respondents age 65 years (RR, 1.19; 95% CI, 1.15 1.23). Among respondents age 65 years, increasing age was associated positively with screening (RR for 5-year interval, 1.49; 95% CI, 1.43 1.57). In respondents age 65
Colorectal Cancer Test Use/Etzioni et al. 2527 TABLE 2 Unadjusted Rates of Recent Colorectal Cancer Testing a,b TABLE 2 Percentage of patients Percentage of patients Ages 50 64 yrs Age > 65 yrs Ages 50 64 yrs Age > 65 yrs Overall 48.0 61.8 Gender Female 43.0 56.4 Male 53.4 69.2 Race White 50.9 63.0 Latino 33.0 51.9 Asian 41.7 55.1 African American 50.1 62.1 Other/multiracial 47.5 61.0 American Indians/Alaska Natives 42.4 63.5 Marital status Married 51.1 66.6 Never married 37.3 55.4 Other (divorced, separated, widowed) 42.3 55.8 Income 300% FPL 52.2 66.4 200 299% FPL 43.9 64.1 100 199% FPL 39.9 56.9 0 99% FPL 31.2 51.8 Education College degree 54.3 68.6 Some college 46.6 63.6 High school 44.1 57.7 High school 34.0 53.7 Self-reported health status Good/very good/excellent 49.1 63.3 Fair/poor 43.4 57.7 Insurance status Respondents ages 50 64 yrs Uninsured 8.2 Medicaid or other public insurance Privately purchased 22.5 Employer-based 23.0 Uninsured 25.7 Medicaid or other public insurance 49.3 Privately purchased 51.1 Employer-based 53.4 Respondents age 65 yrs Uninsured Other Medicare Medicare and Medicaid Medicare and other 30.6 Uninsured Other 60.5 Medicare 54.1 Medicare and Medicaid 54.1 Medicare and other 66.1 No. of visits to physician in last 12 mos None 19.5 25.1 1 2 48.8 62.6 3 4 54.7 64.3 5 9 visits 55.9 65.1 10 visits 54.2 65.5 Percent of life lived in the U.S. 100% 50.2 63.0 51 99% 45.4 59.5 0 50% 33.8 49.1 English proficiency Limited 26.6 45.5 No stated limits 49.5 62.6 FPL: Federal poverty level; USOC: usual source of care. a Data were obtained from the 2001 California Health Interview Survey. b The sample included respondents age 50 years with no personal history of colorectal cancer. c The estimate was not reliable statistically, because there were too few observations. years, this effect reversed direction older respondents were less likely to be screened (RR for 5-year interval, 0.91; 95% CI, 0.88 0.94). Among adults age 65 years, Latinos were the only racial/ethnic group that was significantly less likely than whites to have received recent testing (RR, 0.84; 95% CI, 0.77 0.92). For older individuals, race/ ethnicity was not statistically significant. Income was associated with rates of testing in younger individuals, but not in older individuals. Among adults ages 50 64 years, there was a poverty gradient associated with test use. Respondents living below the FPL were significantly less likely to be tested than the highest income group (RR, 0.81; 95% CI, 0.72 0.91). Respondents in intermediate income groups (100 299% of FPL) had rates of testing between the lowest and the highest income groups. Among older individuals, income level was not found to be predictive of testing. In both age groups, higher levels of education were correlated with a greater likelihood of testing. Health insurance status was a significant predictor of likelihood of testing in both age groups. Table 1 shows that the majority of individuals ages 50 64 years had employer-based insurance with a USOC (65%). For individuals ages 50 64 years with insurance and a USOC, the type of insurance privately purchased, Medicaid, or other public was not predictive of testing compared with individuals who had employment-based insurance and a USOC. Uninsured individuals with a USOC, however, were much less
2528 CANCER December 1, 2004 / Volume 101 / Number 11 TABLE 3 Predictors of Recent Colorectal Cancer Testing a,b TABLE 3 RR (95% CI) RR (95% CI) Ages 50 64 yrs Age > 65 yrs Ages 50 64 yrs Age > 65 yrs Age c 1.49 (1.43 1.57) 0.91 (0.88 0.94) Gender Female 1.00 1.00 Male 1.28 (1.23 1.32) 1.19 (1.15 1.23) Race White 1.00 1.00 Latino 0.84 (0.77 0.92) 0.95 (0.85 1.05) Asian 0.92 (0.84 1.01) 0.98 (0.89 1.05) African American 1.03 (0.94 1.11) 1.04 (0.97 1.11) Other/multiracial 0.96 (0.84 1.08) 1.02 (0.91 1.13) American Indian/Alaska Native 0.93 (0.65 1.22) 1.06 (0.76 1.30) Marital status Married 1.00 1.00 Never married 0.83 (0.75 0.92) 0.88 (0.78 0.97) Other (divorced, separated, widowed) 0.91 (0.86 0.95) 0.93 (0.89 0.96) Income 300% FPL 1.00 1.00 200 299% FPL 0.89 (0.83 0.96) 1.04 (1.00 1.09) 100 199% FPL 0.90 (0.83 0.96) 1.00 (0.95 1.04) 0 99% FPL 0.81 (0.72 0.91) 1.00 (0.94 1.06) Education College degree 1.00 1.00 Some college 0.87 (0.83 0.92) 0.97 (0.93 1.02) High school 0.85 (0.79 0.90) 0.89 (0.85 0.94) High school 0.87 (0.78 0.97) 0.91 (0.85 0.97) Self-reported health status Good/very good/excellent 1.00 1.00 Fair/poor 0.96 (0.91 1.02) 0.92 (0.88 0.96) Insurance status Respondents ages 50 64 yrs Uninsured 0.32 (0.23 0.43) Medicaid or other public insurance 0.54 (0.33 0.82) Privately purchased 0.52 (0.34 0.75) Employer-based 0.53 (0.43 0.63) Uninsured 0.61 (0.53 0.69) Medicaid or other public insurance 1.02 (0.94 1.10) Privately purchased 0.98 (0.91 1.06) Employer-based 1.00 Respondents age 65 yrs Uninsured 0.08 (0.00 1.21) Other 0.51 (0.13 1.14) Medicare 0.41 (0.24 0.64) Medicare and Medicaid 0.59 (0.40 0.81) Medicare and other 0.58 (0.46 0.72) Uninsured 0.62 (0.37 0.92) Other 0.90 (0.81 0.98) Medicare 0.86 (0.79 0.93) Medicare and Medicaid 0.88 (0.83 0.93) Medicare and other 1.00 No. of visits to physician in last 12 mos None 1.00 1.00 1 2 1.55 (1.49 1.61) 1.41 (1.37 1.45) 3 4 1.66 (1.60 1.73) 1.47 (1.42 1.50) 5 9 1.71 (1.64 1.77) 1.46 (1.42 1.50) 10 1.71 (1.64 1.78) 1.48 (1.43 1.51) Percent of life lived in the U.S. 100% 1.00 1.00 51 99% 1.07 (1.00 1.15) 0.96 (0.90 1.02) 0 50% 0.96 (0.87 1.05) 0.86 (0.76 0.97) English proficiency Limited 0.94 (0.82 1.07) 1.00 (0.88 1.11) No stated limits 1.00 1.00 RR: risk ratio; 95% CI: 95% confidence interval; FPL: Federal poverty level; USOC: usual source of care. a Data were obtained from the 2001 California Health Interview Survey. b The sample included respondents age 50 years with no personal history of colorectal cancer. The results are listed as adjusted RRs with 95% confidence intervals. c The age effect is the risk ratio for a 5-year increment (i.e., individuals age 60 years vs. individuals age 55 years). likely to have received testing than individuals who had employer-based insurance with a USOC (RR, 0.61; 95% CI, 0.53 0.69). Individuals ages 50 64 years with no USOC were less likely to be screened than individuals with a USOC and employment-based insurance. The magnitude of this effect was consistent across all other types of insurance (RR range, 0.52 0.54). Individuals who had no insurance and no USOC were far less likely to receive CRC testing (RR, 0.32; 95% CI, 0.23 0.43). Among respondents age 65 years, the majority (71%) had a USOC and Medicare plus supplemental insurance coverage (other than Medicaid) (Table 1). Relative to these individuals, adults with other types of insurance Medicare only or Medicare plus Medicaid were less likely to be tested (RR range, 0.86 0.90) regardless of whether they had a USOC (Table 3). Among younger adults, health status was not predictive of receipt of CRC testing. However, among adults age 65 years, individuals with fair or poor health status were less likely to be tested than individuals with good, very good, or excellent health status (RR, 0.92; 95% CI, 0.88 0.96). Individuals with a greater frequency of visits to a physician in the prior 12 months had a greater likelihood of being screened. This effect was greater among adults ages 50 64 years than among adults age 65 years. Individuals age 65 years who were recent immigrants to the U.S. (0 50% of lifetime in the U.S.)
Colorectal Cancer Test Use/Etzioni et al. 2529 TABLE 4 Reasons for Not Undergoing Colorectal Cancer Testing by Gender and by Race/Ethnicity a,b Response/type examination Row total Male Female White Latino Asian African American Other/multiracial AIAN The physician did not tell me I needed it Endoscopic 26.1 21.6 29.1 c 28.0 22.1 c 21.1 c 24.5 24.8 23.8 FOBT 28.8 25.7 31.3 c 29.3 28.2 25.1 c 32.4 24.7 24.2 No reason Endoscopic 21.7 25.5 19.2 c 20.9 22.2 22.6 27.9 c 22.8 24.2 FOBT 21.8 23.7 20.3 c 21.4 23.1 22.4 22.3 23.9 20.6 Have not had problems Endoscopic 19.6 20.5 19.0 16.1 28.7 c 31.4 c 15.7 20.5 14.0 FOBT 14.5 15.3 13.9 12.1 18.2 c 27.1 c 14.0 14.6 17.4 Did not know a test was needed Endoscopic 7.7 7.3 8.0 7.6 6.8 9.6 8.1 7.4 8.1 FOBT 13.5 13.9 13.1 13.1 16.3 c 13.6 12.0 13.2 14.2 Painful/embarrassing Endoscopic 6.4 3.7 8.2 c 7.8 2.7 c 3.3 c 4.9 c d d FOBT 1.0 0.7 1.3 c 1.1 d d d d d Put it off/laziness Endoscopic 4.1 4.6 3.8 4.7 3.8 d d d d FOBT 3.5 2.8 4.1 c 4.1 1.4 c 1.6 c 4.2 4.9 d Expensive/no insurance Endoscopic 2.9 3.6 2.4 c 2.7 3.8 3.3 d d d FOBT 0.9 0.9 0.9 0.7 1.8 c d d d d Had another type of examination Endoscopic 1.4 1.9 1.0 c 1.6 d d d d d FOBT 4.9 5.4 4.4 c 5.9 1.7 c 2.6 c 3.4 c d d Do not have a physician Endoscopic 0.8 1.3 0.5 c 0.8 d d d d d FOBT 0.6 0.6 0.6 0.6 d d d d d Other Endoscopic 9.3 10.0 8.9 10.0 8.0 6.7 c 8.6 12.2 12.7 FOBT 10.6 11.0 10.3 11.8 7.6 c 5.4 c 10.0 12.7 14.5 AIAN: American Indian/Alaska Native; FOBT: fecal occult blood test; Endoscopic: endoscopic examination. a Data were obtained from the 2001 California Health Interview Survey. b For gender, males and females were compared; for race/ethnicity, comparisons were made with the white reference group. c P values 0.05. d The estimate was not reliable statistically because there were too few observations. were less likely to be tested than lifetime U.S. residents (RR, 0.86; 95% CI, 0.76 0.97). This effect was not present in the younger age group. Limited English proficiency was not a significant predictor of testing for either age group. Reasons for Non-Use of CRC Testing Respondents with no recent FOBT (in the past year) and respondents with no recent endoscopy (in the past 10 years) were asked the main reason why they did not have these tests. Among adults age 50 years who had no personal history of CRC, 17,695 responded to this question regarding FOBT, and 11,945 responded to this question regarding endoscopy. Endoscopic testing The most commonly reported reason respondents did not undergo endoscopic CRC testing was that a physician did not say an examination was needed (Table 4). Other commonly reported reasons were no reason/never thought about it or haven t had any problems. Two-thirds of respondents reported those three reasons. Reported reasons for not having endoscopic testing differed by race and ethnicity. Asians and Latinos were significantly more likely than whites to report that they were not tested because of an absence of symptoms or perceived health problems (Asians, 31%; Latinos, 29%; whites, 16%; P 0.001). The same groups were less likely than whites to report that they were not tested because the endoscopic examination was painful or embarrassing (Asians, 3%; Latinos, 3%; whites, 8%; P 0.001) or because their physician did not tell them the test was needed (Asians, 21%; Latinos, 22%; whites, 28%; P 0.001).
2530 CANCER December 1, 2004 / Volume 101 / Number 11 The reasons reported for not undergoing endoscopic examination also varied by gender. Women were more likely to say that their physician had not informed them they needed the examination (29% vs. 22%; P 0.001). Women also were more than twice as likely as men to perceive endoscopic examinations as painful/embarrassing (8% vs. 4%; P 0. 001), although this was not a commonly mentioned reason for either gender. FOBT testing The reasons identified for not having an FOBT were similar to the reasons for not undergoing endoscopic screening tests, with lack of physician recommendation the most common reason reported by all groups (Table 4). Asians (27%) and Latinos (18%) were significantly more likely than whites (12%; P 0.001) to state an absence of symptoms as the main reason for not having an FOBT. The largest difference between men and women was in the percentage of respondents who reported that a physician did not tell them a test was needed, with women more likely to report this reason than men (31% and 26%, respectively; P 0.001). DISCUSSION The rates of testing for colorectal cancer in the CHIS 2001 were higher compared with the rates seen in recent national health surveys. California, with 54% of its population age 50 years reporting a CRC test in 2001, appears to be ahead of national rates, which were 41% for men and 38% for women in 2000. 7 Although the results of this analysis suggest relatively widespread use of CRC testing in California, two areas require further consideration. First, our results from CHIS were consistent with NHIS data in finding that women were less likely to undergo tests for CRC. One interpretation of this lower use is that women and their health care providers may perceive CRC as less important compared with men and their providers. Women also were more likely than men to say they had not had a recent CRC test, because their physician did not inform them the test was needed or because the tests were painful or embarrassing. The finding that women report using CRC tests less than men in California is somewhat surprising, because cervical and breast cancer screening tests historically have been used widely by women and recommended by their physicians. 3,28 One possible explanation for this finding is that some women use obstetrician/gynecologists as their primary care provider, and it has been shown that physicians in this specialty are much more likely than other primary care physicians to conduct FOBT by digital rectal examination. 29 Digital rectal examination-based FOBT is a nonstandard approach that is discouraged in major guidelines and was not recognized as appropriate testing in the CHIS. The widespread use of other cancer tests suggests that most women already employ cancer screening and readily may accept their physician s recommendation for CRC testing. Professional guidelines and quality-of-care measures are needed to specify appropriate CRC test use. Inclusion of CRC testing as a new Health Plan Employer Data and Information Set measure beginning in 2004 may encourage more providers to recommend CRC testing for their female patients. Further work is needed to understand better the reasons for lower CRC test use among women. A second area of concern is the lower use of CRC tests by Latinos, and especially Latinas. Even after controlling for a broad range of demographic and socioeconomic factors, Latinos ages 50 64 years were less likely to be tested than whites. Disparities for Latinos did not appear to be the result of a language barrier: Respondents with limited proficiency in English did not have worse rates of testing in a comprehensive multivariate model. The reported reasons for not receiving recent CRC screening tests point to possible cultural differences in the perception of how early detection programs work. Latinos and Asians were twice as likely as whites to have stated an absence of symptoms or health problems as the reason for not being tested. With Latinos and Asians, outreach efforts should emphasize the fact that CRC screening is designed for individuals with no symptoms. Our results need to be interpreted in the context of the limitations of the CHIS 2001. The survey was administered by telephone and, thus, may not be as representative of individuals in the lowest socioeconomic strata, who are less likely to have telephone services. However, the CHIS 2001 was weighted to minimize the effects of this characteristic of telephone surveys. 30 Despite its limitations, the CHIS 2001 provides the first adequate sample sizes to develop estimates for Asians and American Indian/Alaska Natives as distinct populations. With future iterations of the CHIS, it will be possible to provide additional clarity in describing population-based uptake of CRC testing in California. What barriers need to be overcome to achieve even greater acceptance for CRC examinations? Having both insurance coverage and a USOC was the most powerful predictor of whether an individual received a CRC test in our analysis. Among insured adults age 50 64 years, Medicaid beneficiaries with a USOC were nearly twice as likely to be tested as Medicaid beneficiaries without a USOC. This finding suggests two
Colorectal Cancer Test Use/Etzioni et al. 2531 policy consequences for Medicaid: First, state policy makers should be aware that ensuring a regular source of care among Medicaid beneficiaries is a policy goal. The ability to maintain a regular source of care for Medicaid beneficiaries is driven largely by the continuity of Medicaid coverage. 31,32 California, as in most other states in times of fiscal distress, exercises budgetary controls by tightening eligibility rules for Medicaid. 33 Requiring beneficiaries to undergo frequent recertification procedures to maintain program eligibility may lead to disruptions in coverage and loss of continuity of care. Second, our results confirmed previous literature in finding insignificant differences in rates of test use between public and private coverage for younger individuals. 34,35 Policies that target increased screening among adults age 65 years should focus on establishing continuous coverage to ensure a regular source of health care, with less attention to uncovering screening differentials between public and private coverage. Underinsurance, however, was a more important issue among the elderly with respect to CRC test use. Low-income elderly without supplemental insurance were less likely to be tested than individuals who were covered by Medicare with supplemental insurance. The last decade has seen a remarkable increase both in the amount of evidence supporting the efficacy of CRC testing and in the acceptance of these examinations. At the time of CHIS 2001, over half of California residents age 50 years had undergone recent testing for CRC. The ongoing challenge remains to provide effective early detection programs to the greatest proportion of the population. Because CRC is preventable, California should be applauded for its achievements and encouraged to continue its efforts. REFERENCES 1. American Cancer Society and Public Health Institute, California Cancer Registry. California cancer facts and figures, 2001. Oakland: American Cancer Society, California Division, 2000. 2. Ries L, Eisner M, Kosary C, et al. SEER cancer statistics review, 1975 2000. Available at: http://seer.cancer.gov/csr/ 1975_2000. 3. Breen N, Wagener DK, Brown ML, Davis WW, Ballard-Barbash R. Progress in cancer screening over a decade: results of cancer screening from the 1987, 1992, and 1998 National Health Interview Surveys. J Natl Cancer Inst. 2001;93:1704 1713. 4. American Cancer Society. Cancer facts and figures, 2003. Atlanta: American Cancer Society, 2003. 5. U.S. Preventive Services Task Force. Screening for colorectal cancer: recommendation and rationale. Ann Intern Med. 2002;137:129 131. 6. Centers for Disease Control and Prevention. Screening for colorectal cancer United States, 1992 1993, and new guidelines. MMWR Morb Mortal Wkly Rep. 1996;45:107 110. 7. Swan J, Breen N, Coates RJ, Rimer BK, Lee NC. Progress in cancer screening practices in the United States: results from the 2000 National Health Interview Survey. Cancer. 2003;97: 1528 1540. 8. O Malley A, Beaton E, Yabroff K, Abramson R, Mandelblatt J. Patient and provider barriers to colorectal cancer screening in the primary care safety-net. Prev Med. 2004;39:56 63. 9. Beeker C, Kraft J, Southwell B, Jorgensen C. Colorectal cancer screening in older men and women: qualitative research findings and implications for intervention. J Commun Health. 2000;25:263 278. 10. Holmes-Rovner M, Williams G, Hoppough S, Quillan L, Butler R, Given C. Colorectal cancer screening barriers in persons with low income. Cancer Pract. 2002;10:240 247. 11. Seeff L, Nadel M, Klabunde C, et al. Patterns and predictors of colorectal cancer test use in the adult U.S. population. Cancer. 2004;100:2093 2103. 12. Greiner K, Engelman K, Hall M, Ellerbeck E. Barriers to colorectal cancer screening in rural primary care. Prev Med. 2004;38:269 275. 13. Mandelson M, Curry S, Anderson L, et al. Colorectal cancer screening participation by older women. Am J Prev Med. 2000;19:149 154. 14. Adams E, Thorpe K, Becker E, Joski P, Flome J. Colorectal cancer screening, 1997 1999: role of income, insurance and policy. Prev Med. 2004;38:551 557. 15. Centers for Disease Control and Prevention. Trends in screening for colorectal cancer United States, 1997 and 1999. MMWR Morb Mortal Wkly Rep. 2001;50:162 166. 16. Ponce NA, Lavarreda SA, Yen W, Brown ER, DiSogra C, Satter D. Translation methodology in the California Health Interview Survey: challenges in language translation for a major survey. Public Health Rep. 2004;119:1 18. 17. California Health Interview Survey. CHIS 2001 methodology series: Report 1 sample design. Los Angeles: UCLA Center for Health Policy Research, 2002. 18. California Health Interview Survey. CHIS 2001 methodology series: Report 2 data collection methods. Los Angeles: UCLA Center for Health Policy Research, 2002. 19. California Health Interview Survey. CHIS 2001 methodology series: Report 3 data processing procedures. Los Angeles: UCLA Center for Health Policy Research, 2002. 20. California Health Interview Survey. CHIS 2001 methodology series: Report 4 response rates. Los Angeles: UCLA Center for Health Policy Research, 2002. 21. Andersen RM, Yu H, Wyn R, Davidson PL, Brown ER, Teleki S. Access to medical care for low-income persons: how do communities make a difference? Med Care Res Rev. 2002;59: 384 411. 22. Seeff LC, Shapiro JA, Nadel MR. Are we doing enough to screen for colorectal cancer? Findings from the 1999 Behavioral Risk Factor Surveillance System. J Fam Pract. 2002;51: 761 766. 23. Shi R, Berkel H, Sartor O. Comparison of utilization of preventive health care services between two racial populations. Ann Epidemiol. 2000;10:454. 24. Corbie-Smith G, Flagg EW, Doyle JP, O Brien MA. Influence of usual source of care on differences by race/ethnicity in receipt of preventive services. J Gen Intern Med. 2002;17: 458 464.
2532 CANCER December 1, 2004 / Volume 101 / Number 11 25. Potosky AL, Breen N, Graubard BI, Parsons PE. The association between health care coverage and the use of cancer screening tests. Results from the 1992 National Health Interview Survey. Med Care. 1998;36:257 270. 26. Maxwell AE, Bastani R, Warda US. Demographic predictors of cancer screening among Filipino and Korean immigrants in the United States. Am J Prev Med. 2000;18:62 68. 27. Zhang J, Yu KF. What s the relative risk? A method of correcting the odds ratio in cohort studies of common outcomes. JAMA. 1998;280:1690 1691. 28. Augustson EM, Vadaparampil ST, Paltoo DN, Kidd LR, O Malley AS. Association between CBE, FOBT, and Pap smear adherence and mammography adherence among older low-income women. Prev Med. 2003;36:734 739. 29. Klabunde CN, Frame PS, Meadow A, Jones E, Nadel M, Vernon SW. A national survey of primary care physicians colorectal cancer screening recommendations and practices. Prev Med. 2003;36:352 362. 30. Centers for Disease Control and Prevention. Colorectal cancer prevention and control initiatives. Available from URL: http://www.cdc.gov/cancer/colorctl/ [accessed October 16, 2003]. 31. California Health Interview Survey. CHIS 2001 methodology series: Report 5 weighting and variance estimation. Los Angeles: UCLA Center for Health Policy Research, 2002. 32. Newacheck PW, Pearl M, Hughes DC, Halfon N. The role of Medicaid in ensuring children s access to care. JAMA. 1998; 280:1789 1793. 33. Kasper JD, Giovannini TA, Hoffman C. Gaining and losing health insurance: strengthening the evidence for effects on access to care and health outcomes. Med Care Res Rev. 2000;57:298 318; discussion, 319 225. 34. Kaiser Family Foundation. News on Medicaid and state budgets: July and August 2003 update. Available from URL: http://www.kff.org/medicaid/kcmu4140report.cfm [accessed August 16, 2003]. 35. Chimento L, Forbes M, Menges J, Theisen A, Pande N. Simplifying Medi-Cal enrollment: opportunities and challenges in tight fiscal times. Medi-Cal Policy Inst Issue Brief. 2003;6:1 12.