Young Kyung Do

Hidden barriers between knowledge and behavior: the North Carolina prostate cancer screening and treatment experience.

Prostate cancer (PC) mortality is much greater for African American than for Caucasian men. To identify patient factors that might account for some of this disparity, men within 6 months of diagnosis were surveyed about health attitudes and behavior.

The associations between self-reported sleep duration and adolescent health outcomes: What is the role of time spent on Internet use?

OBJECTIVE This study aimed to examine the associations of self-reported sleep duration with adolescent health outcomes, taking into account time spent on Internet use. METHODS We used data from the 2008-2009 Korea Youth Behavioral Risk Factor Survey, a cross-sectional online survey of middle and high school students aged 13-18years in South Korea (N=136,589) to examine the associations of self-reported sleep duration with four mental and physical health measures, e.g. self-report of depressive symptoms, suicidal ideation, weight status, and self-rated health. The binary logit and generalized ordered logit models controlled for time spent on Internet use for non-study purposes and other factors. RESULTS Shorter self-reported sleep duration was associated with a higher likelihood of reporting depressive symptoms, suicidal ideation, and overweight or obese status, and a lower likelihood of reporting better self-rated health, even after accounting for time spent on Internet use. Excessive Internet use was found to be an independent risk factor for these outcomes. CONCLUSIONS Among in-school adolescents in South Korea, shorter sleep duration and excessive Internet use are independently and additively associated with multiple indicators of adverse health status. Excessive Internet use may have not only direct adverse health consequences, but also have indirect negative effects through sleep deprivation.

Cost-effectiveness of epidermal growth factor receptor mutation testing and first-line treatment with gefitinib for patients with advanced adenocarcinoma of the lung

Epidermal growth factor receptor (EGFR) testing and first‐line therapy with gefitinib for patients with activating mutations is quickly becoming the standard option for the treatment of advanced lung adenocarcinoma. Yet, to date, little is known about the cost‐effectiveness of this approach.

Race, healthcare access and physician trust among prostate cancer patients

ObjectiveTo study the effect of healthcare access and other characteristics on physician trust among black and white prostate cancer patients.MethodsA three-timepoint follow-up telephone survey after cancer diagnosis was conducted. This study analyzed data on 474 patients and their 1,320 interviews over three time periods.ResultsAmong other subpopulations, black patients who delayed seeking care had physician trust levels that were far lower than that of both Caucasians as well as that of the black patients overall. Black patients had greater variability in their levels of physician trust compared to their white counterparts.ConclusionsBoth race and access are important in explaining overall lower levels and greater variability in physician trust among black prostate cancer patients. Access barriers among black patients may spill over to the clinical encounter in the form of less physician trust, potentially contributing to racial disparities in treatment received and subsequent outcomes. Policy efforts to address the racial disparities in prostate cancer should prioritize improving healthcare access among minority groups.

Informal Care and Caregiver's Health

This study aims to measure the causal effect of informal caregiving on the health and health care use of women who are caregivers, using instrumental variables. We use data from South Korea, where daughters and daughters-in-law are the prevalent source of caregivers for frail elderly parents and parents-in-law. A key insight of our instrumental variable approach is that having a parent-in-law with functional limitations increases the probability of providing informal care to that parent-in-law, but a parent-in-laws functional limitation does not directly affect the daughter-in-laws health. We compare results for the daughter-in-law and daughter samples to check the assumption of the excludability of the instruments for the daughter sample. Our results show that providing informal care has significant adverse effects along multiple dimensions of health for daughter-in-law and daughter caregivers in South Korea.

The Effect of Coresidence With an Adult Child on Depressive Symptoms Among Older Widowed Women in South Korea: An Instrumental Variables Estimation

OBJECTIVES To estimate the causal effect of coresidence with an adult child on depressive symptoms among older widowed women in South Korea. METHOD Data from the first (2006) and second (2008) waves of the Korea Longitudinal Study of Ageing were used. The analysis was restricted to widowed women aged ≥65 years with at least one living child (N = 2,446). We used an instrumental variables (IVs) estimation exploiting two child characteristics as IVs (the number of sons and whether the eldest child is a daughter). Specification tests for IVs showed that these instruments predict the probability of an older widowed womans coresidence with an adult child but do not directly affect depressive symptoms. RESULTS Our IV two-stage least-squares estimator suggested that coresidence with an adult child has a protective effect on depressive symptoms among older widowed women in South Korea. Coresidence was found to be endogenous in our statistical model of depressive symptoms. DISCUSSION The IV estimation method can be a useful approach to addressing the potential endogeneity between intergenerational coresidence and elderly health. Rapidly decreasing rates of intergenerational coresidence may raise public health concerns among older widowed women in South Korea.

Educational disparities in quality of diabetes care in a universal health insurance system: evidence from the 2005 Korea National Health and Nutrition Examination Survey

OBJECTIVE To investigate educational disparities in the care process and health outcomes among patients with diabetes in the context of South Koreas universal health insurance system. DESIGN Bivariate and multiple regression analyses of data from a cross-sectional health survey. SETTING A nationally representative and population-based survey, the 2005 Korea National Health and Nutrition Examination Survey. PARTICIPANTS Respondents aged 40 or older who self-reported prior diagnosis with diabetes (n= 1418). MAIN OUTCOME MEASURES Seven measures of the care process and health outcomes, namely (i) receiving medical treatment for diabetes, (ii) ever received diabetes education, (iii) received dilated eye examination in the past year, (iv) received microalbuminuria test in the past year, (v) having activity limitation due to diabetes, (vi) poor self-rated health and (vii) self-rated health on a visual analog scale. RESULTS Except for receiving medical care for diabetes, overall process quality was low, with only 25% having ever received diabetes education, 39% having received a dilated eye examination in the past year and 51% having received a microalbuminuria test in the past year. Lower education level was associated with both poorer care processes and poorer health outcomes, whereas lower income level was only associated with poorer health outcomes. CONCLUSION While South Koreas universal health insurance system may have succeeded in substantially reducing financial barriers related to diabetes care, the quality of diabetes care is low overall and varies by education level. System-level quality improvement efforts are required to address the weaknesses of the health system, thereby mitigating educational disparities in diabetes care quality.

Perceived family history risk and symptomatic diagnosis of prostate cancer: the North Carolina Prostate Cancer Outcomes study.

Prostate cancer (PrCA) is the most common cancer and the second leading cause of cancer death among US men. African American (AA) men remain at significantly greater risk of PrCA diagnosis and mortality than other men. Many factors contribute to the experienced disparities.

A quantile regression analysis of ambulance response time.

Abstract Background. Shorter ambulance response time (ART) contributes to improved clinical outcomes. Various methods have been used to analyze ART. Objectives. We aimed to compare the use of quantile regression with the standard ordinary least squares (OLS) model for identifying factors associated with ART in Singapore. A secondary aim was to determine the relative importance of patient-level (e.g., gender and ethnicity) versus system-level (e.g., call volumes within the last one hour) factors contributing to longer ART. Methods. We conducted a retrospective review of data electronically captured from ambulance dispatch records and patient case notes of emergency calls to the national ambulance service from January to May 2006 (n = 30,687). The primary outcome was ART, defined as the time taken for an ambulance to arrive at the scene upon receiving an emergency call, and modeled as a function of patient- and system-level factors. We used a quantile regression model to account for potential heterogeneous effects of explanatory variables on ART across different quantiles of the ART distribution, and compared estimates derived with the corresponding OLS estimates. Results. Quantile regression estimates suggested that the call volume in the previous one hour predicted increased ART, with the effect being more pronounced in higher ART quantiles. At the 90th and 50th percentiles of ART, each additional call in the last one hour was predicted to increase ART to the next call from the same area by 93 and 57 seconds, respectively. The corresponding OLS estimate was 58 seconds. Patient factors had little effect on ART. Conclusion. The quantile regression model is more useful than the OLS model for estimating ART, revealing that in Singapore, ART is influenced heterogeneously by the volume of emergency calls in the past one hour.

Awareness and acceptability of human papillomavirus vaccine: an application of the instrumental variables bivariate probit model

BackgroundAlthough lower uptake rates of the human papillomavirus (HPV) vaccine among socioeconomically disadvantaged populations have been documented, less is known about the relationships between awareness and acceptability, and other factors affecting HPV vaccine uptake.The current study aimed to estimate the potential effectiveness of increased HPV vaccine awareness on the acceptability of HPV vaccination in a nationally representative sample of women, using a methodology that controlled for potential non-random selection.MethodsThis study used a population-based sample from the 2007 Health Information National Trends Survey, a cross-sectional study of the US population aged 18 years or older, and focused on the subsample of 742 women who have any female children under the age of 18 years in the household. An instrumental variables bivariate probit model was used to jointly estimate HPV vaccine awareness and acceptability.ResultsThe proportion of HPV vaccine acceptability among the previously aware and non-aware groups was 58% and 47%, respectively. Results from the instrumental variables bivariate probit model showed that the estimated marginal effect of awareness on acceptability was 46 percentage points, an effect that was even greater than observed.ConclusionsAmong populations who are not currently aware of the HPV vaccine, the potential impact of raising awareness on acceptability of HPV vaccination is substantial. This finding provides additional support to strengthening public health programs that increase awareness and policy efforts that address barriers to HPV vaccination.