YunKyung Chang

Intensity-Modulated Radiation Therapy, Proton Therapy, or Conformal Radiation Therapy and Morbidity and Disease Control in Localized Prostate Cancer

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 for primary prostate cancer treatment. DESIGN, SETTING, AND PATIENTS Population-based study using Surveillance, Epidemiology, and End Results-Medicare-linked data from 2000 through 2009 for patients with nonmetastatic prostate cancer. MAIN OUTCOME MEASURES Rates of gastrointestinal and urinary morbidity, erectile dysfunction, hip fractures, and additional cancer therapy. RESULTS Use of IMRT vs conformal radiation therapy increased from 0.15% in 2000 to 95.9% in 2008. In propensity score-adjusted analyses (N = 12,976), men who received IMRT vs conformal radiation therapy were less likely to receive a diagnosis of gastrointestinal morbidities (absolute risk, 13.4 vs 14.7 per 100 person-years; relative risk [RR], 0.91; 95% CI, 0.86-0.96) and hip fractures (absolute risk, 0.8 vs 1.0 per 100 person-years; RR, 0.78; 95% CI, 0.65-0.93) but more likely to receive a diagnosis of erectile dysfunction (absolute risk, 5.9 vs 5.3 per 100 person-years; RR, 1.12; 95% CI, 1.03-1.20). Intensity-modulated radiation therapy patients were less likely to receive additional cancer therapy (absolute risk, 2.5 vs 3.1 per 100 person-years; RR, 0.81; 95% CI, 0.73-0.89). In a propensity score-matched comparison between IMRT and proton therapy (n = 1368), IMRT patients had a lower rate of gastrointestinal morbidity (absolute risk, 12.2 vs 17.8 per 100 person-years; RR, 0.66; 95% CI, 0.55-0.79). There were no significant differences in rates of other morbidities or additional therapies between IMRT and proton therapy. CONCLUSIONS Among patients with nonmetastatic prostate cancer, the use of IMRT compared with conformal radiation therapy was associated with less gastrointestinal morbidity and fewer hip fractures but more erectile dysfunction; IMRT compared with proton therapy was associated with less gastrointestinal morbidity.

Exploring organizational context and structure as predictors of medication errors and patient falls

Objectives: To examine relationships among organizational context (characteristics of the external, hospital, and nursing unit environments), organizational structure (unit capacity, work engagement, and work conditions), patient characteristics (age, sex, and health status), safety climate, and effectiveness (medication errors and falls) in acute care hospitals. Methods: Data came from 278 medical-surgical units at 143 hospitals that participated in the Outcomes Research in Nursing Administration Project II, a longitudinal multisite study. Results: Selected measures of the external, hospital, and nursing unit environment had significant influences on the organizational structure of nursing units, which in turn significantly predicted unit-level safety climate. However, structural measures had limited effects on medication errors and falls. Patient age and health status were associated with falls but not with medication errors. There was a significant structure-safety climate interaction, where units with higher levels of unit capacity but lower levels of safety climate reported fewer medication errors. In contrast, units with higher levels of unit capacity and higher levels of safety climate reported more falls. Conclusions: There are important influences of contextual, structural, and safety climate factors on both medication errors and falls. The limited effect of structure on effectiveness and the differential moderating effect of safety climate suggest that future studies may benefit from the use of theoretical models that are targeted more specifically to the explanation of a particular type of adverse event.

A systematic review comparing antiretroviral adherence descriptive and intervention studies conducted in the USA

Abstract We examined the extent to which studies aimed at testing interventions to improve antiretroviral adherence have targeted the facilitators of and barriers known to affect adherence. Of the 88 reports reviewed, 41 were reports of descriptive studies conducted with US HIV-positive women and 47 were reports of intervention studies conducted with US HIV-positive persons. We extracted from the descriptive studies all findings addressing any factor linked to antiretroviral adherence and from the intervention studies, information on the nature of the intervention, the adherence problem targeted, the persons targeted for the intervention, and the intervention outcomes desired. We discerned congruence between the prominence of substance abuse as a factor identified in the descriptive studies as a barrier to adherence and its prominence as the problem most addressed in those reports of intervention studies that specified the problems targeted for intervention. We also discerned congruence between the prominence of family and provider support as factors identified in the descriptive studies as facilitators of adherence and the presence of social support as an intervention component and outcome variable. Less discernible in the reports of intervention studies was specific attention to other factors prominent in the descriptive studies, which may be due to the complex nature of the problem, individualistic and rationalist slant of interventions, or simply the ways interventions were presented. Our review raises issues about niche standardization and intervention tailoring, targeting, and fidelity.

Transforming Verbal Counts in Reports of Qualitative Descriptive Studies Into Numbers

Reports of qualitative studies typically do not offer much information on the numbers of respondents linked to any one finding. This information may be especially useful in reports of basic, or minimally interpretive, qualitative descriptive studies focused on surveying a range of experiences in a target domain, and its lack may limit the ability to synthesize the results of such studies with quantitative results in systematic reviews. Accordingly, the authors illustrate strategies for deriving plausible ranges of respondents expressing a finding in a set of reports of basic qualitative descriptive studies on antiretroviral adherence and suggest how the results might be used. These strategies have limitations and are never appropriate for use with findings from interpretive qualitative studies. Yet they offer a temporary workaround for preserving and maximizing the value of information from basic qualitative descriptive studies for systematic reviews. They show also why quantitizing is never simply quantitative.

Combining adjusted and unadjusted findings in mixed research synthesis

RATIONALE, AIMS AND OBJECTIVES Finding ways to incorporate disparate types of evidence into research syntheses has the potential to build a better evidence base for clinical practice and policy. Yet conducting such mixed research synthesis studies is challenging. Researchers have to determine whether and how to use adjusted and unadjusted quantitative findings in combination with each other and with qualitative findings. METHODS Among quantitative findings, adjustment for confounding, either via study design or statistical analysis, can be a considerable source of heterogeneity. Yet there is no consensus about the best way to synthesize findings resulting from different methods for addressing confounding. When synthesizing qualitative and quantitative findings, additional considerations include determining whether findings are amenable to synthesis by aggregation or configuration, which, in turn, depends on the degree of interpretive transformation of findings. RESULTS Qualitative survey findings appear similar in form to unadjusted or minimally adjusted quantitative findings and, when addressing the same relationship, can be summed. More interpreted qualitative findings appear similar in form to adjusted findings found in, for example, structural equation models specifying the relationship among a host of latent variables. An option for synthesis of conceptually similar models is reciprocal translation. CONCLUSIONS These decisions will ultimately be judged on the meaningfulness of their results to practice or policy.

A Bayesian method for the synthesis of evidence from qualitative and quantitative reports: the example of antiretroviral medication adherence

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 quantitative evidence in the likelihood in a Bayesian synthesis of evidence about the relationship between regimen complexity and medication adherence. Methods: Data were from 11 qualitative and six quantitative studies. We updated two different non-informative prior distributions with qualitative and quantitative findings to find the posterior distribution for the probabilities that a more complex regimen was associated with lower adherence and that a less complex regimen was associated with greater adherence. Results: The posterior mode for the qualitative findings regarding more complex regimen and lesser adherence (using the uniform prior with Jeffreys’ prior yielding highly similar estimates) was 0.588 (95% credible set limits 0.519, 0.663) and for the quantitative findings was 0.224 (0.203, 0.245); due to non-overlapping credible sets, we did not combine them. The posterior mode for the qualitative findings regarding less complex regimen and greater adherence was 0.288 (0.214, 0.441) and for the quantitative findings was 0.272 (0.118, 0.437); the combined estimate was 0.299 (0.267, 0.334). Conclusions: The utility of Bayesian methods for synthesizing qualitative and quantitative research findings at the participant level may depend on the nature of the relationship being synthesized and on how well the findings are represented in the individual reports.

Sorafenib Effectiveness in Advanced Hepatocellular Carcinoma

Survival after sorafenib initiation in newly diagnosed Medicare beneficiaries with hepatocellular carcinoma (HCC) is exceptionally short, suggesting that trial results are not generalizable to all HCC patients. The downsides of sorafenib use—high drug-related symptom burden and high drug cost—must be considered in light of this minimal benefit.

Improving our understanding of the surgical oncology workforce.

Objective:This study characterizes the surgical oncology workforce as a baseline for future workforce projections. Background:Measuring the capacity of the surgical oncology workforce is difficult due to the wide variety of surgeons who contribute to surgical cancer care. We hypothesize that the bulk of surgical oncology care is provided by general surgeons. Methods:Using Medicare claims data linked to the North Carolina Central Cancer Registry, all patients 65 years or older who had a diagnosis of incident cancer of the bladder, breast, colon/rectum, esophagus, gallbladder, kidney, liver, lung, skin (melanoma-only), ovary, pancreas, prostate, small bowel, stomach, or uterus in 2005 and who underwent an extirpative procedure for cancer were identified. The proportion of procedures performed by different types of providers was examined. Results:A total of 7759 patients underwent 16,734 extirpative surgical procedures. Excluding procedures for gynecologic/urologic malignancies, the proportion of procedures performed by general surgeons and surgical oncologists was 48% and 12%, respectively. Patients treated by general surgeons were more likely to be older, female, minority, and from areas of high poverty. For each tumor type, travel distances were shorter for patients treated by general surgeons than those treated by specialists. Conclusions:Workforce projections must account for the significant overlap in the scope of services delivered by providers of different specialties and for the large contribution of general surgeons to cancer care. Efforts to improve the quality of cancer care need to move beyond centralization and focus on educating the surgeons who are providing the bulk of oncology care.

Frailty index developed from a cancer-specific geriatric assessment and the association with mortality among older adults with cancer

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 Methods: Using a unique and novel data set that brings together GA data with cancer-specific and long-term mortality data, we developed the Carolina Frailty Index (CFI) from a cancer-specific GA based on the principles of deficit accumulation. CFI scores (range, 0-1) were categorized as robust (0-0.2), pre-frail (0.2-0.35), and frail (>0.35). The primary outcome for evaluating predictive validity was all-cause mortality. The Kaplan-Meier method and log-rank tests were used to compare survival between frailty groups, and Cox proportional hazards regression models were used to evaluate associations. Results: In our sample of 546 older adults with cancer, the median age was 72 years, 72% were women, 85% were white, and 47% had a breast cancer diagnosis. Overall, 58% of patients were robust, 24% were pre-frail, and 18% were frail. The estimated 5-year survival rate was 72% in robust patients, 58% in pre-frail patients, and 34% in frail patients (log-rank test, P<.0001). Frail patients had more than a 2-fold increased risk of all-cause mortality compared with robust patients (adjusted hazard ratio, 2.36; 95% CI, 1.51-3.68). Conclusions: The CFI was predictive of all-cause mortality in older adults with cancer, a finding that was independent of age, sex, cancer type and stage, and number of medical comorbidities. The CFI has the potential to become a tool that oncologists can use to objectively identify frailty in older adults with cancer.

Data Linkage to Improve Geriatric Oncology Research: A Feasibility Study

The development of a more robust observational research data infrastructure would help to address gaps in the evidence base regarding optimal approaches to treating cancer among the growing and complex population of older adults. To demonstrate the feasibility of building such a resource, information from a sample of older adults with cancer was linked using three distinct but complementary data sources. Results are reported to highlight the potential for data linkage to improve the characterization of health status among older adults with cancer and the possibility to conduct passive follow‐up for outcomes of interest over time.