Yunkyung Chang

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CONTEXT There has been rapid adoption of newer radiation treatments such as intensity-modulated radiation therapy (IMRT) and proton therapy despite greater cost and limited demonstrated benefit compared with previous technologies. OBJECTIVE To determine the comparative morbidity and disease control of IMRT, proton therapy, and conformal radiation therapy(More)
PURPOSE Travel distances to care have increased substantially with centralization of complex cancer procedures at high-volume centers. We hypothesize that longer travel distances are associated with higher rates of postoperative readmission and poorer outcomes. METHODS SEER-Medicare patients with bladder, lung, pancreas, or esophagus cancer who were(More)
PURPOSE To investigate if differences in antecedents of severe and nonsevere medication errors exist. DESIGN A longitudinal study of 6 months of data from 279 nursing units in 146 randomly selected hospitals in the United States (US). METHODS Antecedents of severe and nonsevere medication errors included work environment factors (work dynamics and RN(More)
Over the last decade, there has been increased attention to the role of earlier HIV testing in the United States. Our objective was to determine if this has translated into changes in the proportion of inpatients with advanced disease at the time of initial HIV diagnosis. We identified inpatients discharged with a new diagnosis of HIV infection or AIDS(More)
BACKGROUND Describing the safety climate in hospitals is an important first step in creating work environments where safety is a priority. Yet, little is known about the patient safety climate on medical-surgical units. PURPOSES Study purposes were to describe quality and strength of the patient safety climate on medical-surgical units and explore(More)
Background: An objective measure is needed to identify frail older adults with cancer who are at increased risk for poor health outcomes. The primary objective of this study was to develop a frailty index from a cancer-specific geriatric assessment (GA) and evaluate its ability to predict all-cause mortality among older adults with cancer. Patients and(More)
BACKGROUND Phase III trials show sorafenib improves survival in advanced hepatocellular carcinoma (HCC). Because of narrow trial eligibility, results may not be generalizable to a broader HCC population. We sought to evaluate the effectiveness of initial sorafenib versus no treatment among Medicare beneficiaries with advanced HCC. MATERIALS AND METHODS(More)
PROBLEM Hospital nurses have one of the highest work-related injury rates in the United States. Yet, approaches to improving employee safety have generally focused on attempts to modify individual behavior through enforced compliance with safety rules and mandatory participation in safety training. We examined a theoretical model that investigated the(More)
OBJECTIVES Bayesian meta-analysis is a frequently cited but very little-used method for synthesizing qualitative and quantitative research findings. The only example published to date used qualitative data to generate an informative prior probability and quantitative data to generate the likelihood. We developed a method to incorporate both qualitative and(More)
BACKGROUND Despite increasing recognition of the significance of learning from errors, little is known about how learning climate contributes to error reduction. OBJECTIVES The purpose of this study was to investigate whether learning climate moderates the relationship between error-producing conditions and medication errors. METHODS A cross-sectional(More)