Hongjian Yu

Access to Medical Care for Low-Income Persons: How do Communities Make a Difference?

This paper considers the impact of community-level variables over and above the effects of individual characteristics on healthcare acess for low-income children and adults residing in large metropolitan statistical areas (MSAs). Further, we rank MSAs’ performance in promoting healthcare access for their low-income populations. The individual-level data come from the 1995 and 1996 National Health Interview Survey (NHIS). The community-level variables are derived from multiple public-use data sources. The out-come variable is whether low-income individuals received a physician visit in the past twelve months. The proportion receiving a visit by MSA varied from 63% to 99% for children and from 62% to 83% for adults. Access was better for individuals with health insurance and a regular source of care and for those living in communities with more federally-funded health centers. Children residing in MSA

A population‐based survey of prostate‐specific antigen testing among California men at higher risk for prostate carcinoma

Despite the lack of evidence demonstrating a survival benefit from prostate‐specific antigen (PSA) screening, its use has become widespread, organizations have encouraged physicians to discuss early detection of prostate carcinoma, and two higher risk groups have been recognized. In the current study, the authors examined whether African‐American men and men who had a family history of prostate carcinoma underwent PSA testing preferentially, and patterns of test use were examined according to age, race, and other factors.

Effects of Community Factors on Access to Ambulatory Care for Lower-Income Adults in Large Urban Communities:

This study examines the effects of community-level and individual-level factors on access to ambulatory care for lower-income adults in 54 urban metropolitan statistical areas in the United States. Drawing on a conceptual behavioral and structural framework of access, the authors developed multivariate models for insured and uninsured lower-income adults to assess the adjusted effects of community- and individual-level factors on two indicators of access: having a usual source of care, and having at least one physician visit in the past year. Several community factors influenced access, but they did so differently for insured and uninsured adults and for the two measures of access used. The findings of this study confirm that public policies and community environment have measurable and substantial impacts on access to care, and that expanded public resources, such as Medicaid payments and safety-net clinics, can lead to measurable improvements in access for vulnerable populations residing in large urban areas.

WHO IS USING EMERGENCY CONTRACEPTION? Awareness and Use of Emergency Contraception Among California Women and Teens

INTRODUCTION Emergency contraception (EC) reduces womens risk for pregnancy after unprotected intercourse, and womens awareness of the method is increasingly important for expanding access. However, knowledge of EC alone does not predict use, and few population data exist to describe EC use among those aware of the method. METHODS Using data from the 2003 California Health Interview Survey, we measured EC awareness among 11,392 women ages 15-44, and EC use among 7,178 respondents who were aware of EC and at risk for pregnancy. Using chi(2) analyses and multivariable logistic regression, we examined population characteristics that epidemiologically predict EC awareness and use, including age, race/ethnicity, income, health insurance status, usual source of health care, immigration status, languages spoken at home, and urban versus rural residence. RESULTS Nearly 76% of respondents had heard of EC, but awareness was lower among teens, women of color, poor women, women with publicly funded health insurance, those without a usual source of care, immigrants, non-English-language speakers, and rural residents. Among women aware of EC, about 4% reported having used the method in the previous year; young age, low income, attending a community/government clinic for care or not having a source of care, and living in an urban area significantly increased the odds for using EC. CONCLUSIONS Among California women in 2003, awareness and use of EC remained low. However, similar rates of use were reported among racial, ethnic, and linguistic subgroups. Those most likely to report use of the method included population groups at high risk for unintended pregnancy.

Perceptions of health and use of ambulatory care: Differences between Korean and White elderly.

This study identifies whether culturally based differences in perceptions of health resulted in differences in ambulatory care use among the elderly. Methods:The authors conducted stratified Poisson regressions on data from a 1992 survey of older Koreans and Whites in Los Angeles County. The models included measures of demographics, health, functioning, income, insurance, social support, and culture (perceptions of health or other beliefs). Results:Descriptive findings showed older Koreans had more ambulatory physician visits, poorer functioning, and poorer perceptions of their health than Whites. Multivariate findings showed that positive perceptions of health independently reduced office visits for bothKoreans and Whites, but the effect was significantly smaller for Koreans. Other cultural differences also affected use. Discussion:The findings highlight differences between older Koreans and Whites’ responses to physical and socioeconomic conditions and the importance of cultural sensitivity in the health care delivery system.

Small-Area Estimation of Health Insurance Coverage for California Legislative Districts

OBJECTIVES To aid state and local policymakers, program planners, and community advocates, we created estimates of the percentage of the population lacking health insurance in small geographic areas of California. METHODS Finally, calibration ensured the consistency and stability of the estimates when they were aggregated. RESULTS Health insurance coverage among nonelderly persons varied widely across assembly districts, from 10% to 44%. The utility of local-level estimates was most apparent when the variations in subcounty uninsured rates in Los Angeles County (19%-44%) were examined. CONCLUSIONS Stable and useful estimates of health insurance rates for small areas such as legislative districts can be created through use of multiple sources of publicly available data.

A Comparison of Hispanic and White Adolescent Females' Use of Family Planning Services in California

CONTEXT In California, the adolescent birthrate among Hispanics is three times that among whites. Because Hispanics are projected to make up one-half of the states adolescents by 2020, it is important to determine how cultural and health policy-relevant factors are linked to this groups use of family planning services. METHODS Data from the 2001 California Health Interview Survey were used to examine characteristics of Hispanic and white females aged 14-17, including patterns of use of family planning services in the past year. Multivariate logistic regression analyses were conducted to assess the association between selected characteristics and use of family planning services. RESULTS Compared with white adolescents, Hispanic adolescents came from poorer families, had a poorer health status, less commonly had a regular source of primary health care and had lower rates of alcohol and drug use, and of sexual experience. Although the proportion of sexually experienced Hispanics who had used family planning services was similar to that of whites (34% and 27%, respectively), the proportion who had ever been pregnant and used such services was significantly larger (42% vs. 9%). In the multivariate analysis, Hispanic adolescents who had ever been pregnant were significantly more likely than whites who had not to have used family planning services in the past year (odds ratio, 11.6). CONCLUSIONS A need exists for family planning programs to target Hispanic adolescents before they become pregnant, and to send a clear message that contraceptive services are available and should be used before a woman ever has a pregnancy.

Reach of Supplemental Nutrition Assistance Program - Education (SNAP-Ed) Interventions and Nutrition and Physical Activity-Related Outcomes, California, 2011 - 2012

Introduction This study combined information on the interventions of the US Department of Agriculture’s Supplemental Nutrition Assistance Program–Education with 5,927 interview responses from the California Health Interview Survey to investigate associations between levels of intervention reach in low-income census tracts in California and self-reported physical activity and consumption of fruits and vegetables, fast food, and sugar-sweetened beverages. Methods We determined 4 levels of intervention reach (low reach, moderate reach, high reach, and no intervention) across 1,273 program-eligible census tracts from data on actual and eligible number of intervention participants. The locations of California Health Interview Survey respondents were geocoded and linked with program data. Regression analyses included measures for sex, age, race/ethnicity, and education. Results Adults and children from high-reach census tracts reported eating more fruits and vegetables than adults and children from no-intervention census tracts. Adults from census tracts with low, moderate, or high levels of reach reported eating fast food less often than adults from no-intervention census tracts. Teenagers from low-reach census tracts reported more physical activity than teenagers in no-intervention census tracts. Conclusion The greatest concentration of Supplemental Nutrition Assistance Program–Education interventions was associated with adults and children eating more fruits and vegetables and adults eating fast food less frequently. These findings demonstrate the potential impact of such interventions as implemented by numerous organizations with diverse populations; these interventions can play an important role in addressing the obesity epidemic in the United States. Limitations of this study include the absence of measures of exposure to the intervention at the individual level and low statistical power for the teenager sample.

Generating Health Estimates by Zip Code: A Semiparametric Small Area Estimation Approach Using the California Health Interview Survey

OBJECTIVES We propose a method to meet challenges in generating health estimates for granular geographic areas in which the survey sample size is extremely small. METHODS Our generalized linear mixed model predicts health outcomes using both individual-level and neighborhood-level predictors. The models feature of nonparametric smoothing function on neighborhood-level variables better captures the association between neighborhood environment and the outcome. Using 2011 to 2012 data from the California Health Interview Survey, we demonstrate an empirical application of this method to estimate the fraction of residents without health insurance for Zip Code Tabulation Areas (ZCTAs). RESULTS Our method generated stable estimates of uninsurance for 1519 of 1765 ZCTAs (86%) in California. For some areas with great socioeconomic diversity across adjacent neighborhoods, such as Los Angeles County, the modeled uninsured estimates revealed much heterogeneity among geographically adjacent ZCTAs. CONCLUSIONS The proposed method can increase the value of health surveys by providing modeled estimates for health data at a granular geographic level. It can account for variations in health outcomes at the neighborhood level as a result of both socioeconomic characteristics and geographic locations.