Yoonsang Kim

Prevalence estimates for primary brain tumors in the United States by age, gender, behavior, and histology

Prevalence is the best indicator of cancer survivorship in the population, but few studies have focused on brain tumor prevalence because of previous data limitations. Hence, the full impact of primary brain tumors on the healthcare system in the United States is not completely described. The present study provides an estimate of the prevalence of disease in the United States, updating an earlier prevalence study. Incidence data for 2004 and survival data for 1985-2005 were obtained by the Central Brain Tumor Registry of the United States from selected regions, modeled under 2 different survival assumptions, to estimate prevalence rates for the year 2004 and projected estimates for 2010. The overall incidence rate for primary brain tumors was 18.1 per 100 000 person-years with 2-, 5-, 10-, and 20-year observed survival rates of 62%, 54%, 45%, and 30%, respectively. On the basis of the sum of nonmalignant and averaged malignant estimates, the overall prevalence rate of individuals with a brain tumor was estimated to be 209.0 per 100 000 in 2004 and 221.8 per 100 000 in 2010. The female prevalence rate (264.8 per 100 000) was higher than that in males (158.7 per 100 000). The averaged prevalence rate for malignant tumors (42.5 per 100 000) was lower than the prevalence for nonmalignant tumors (166.5 per 100 000). This study provides estimates of the 2004 (n = 612 770) and 2010 (n = 688 096) expected number of individuals living with primary brain tumor diagnoses in the United States, providing more current and robust estimates for aiding healthcare planning and patient advocacy for an aging US population.

The Effects of Smoking-Related Television Advertising on Smoking and Intentions to Quit Among Adults in the United States: 1999–2007

OBJECTIVES We investigated whether state-sponsored antitobacco advertisements are associated with reduced adult smoking, and interactions between smoking-related advertising types. METHODS We measured mean exposure to smoking-related advertisements with television ratings for the top-75 US media markets from 1999 to 2007. We combined these data with individual-level Current Population Surveys Tobacco Use Supplement data and state tobacco control policy data. RESULTS Higher exposure to state-sponsored, Legacy, and pharmaceutical advertisements was associated with less smoking; higher exposure to tobacco industry advertisements was associated with more smoking. Higher exposure to state- and Legacy-sponsored advertisements was positively associated with intentions to quit and having made a past-year quit attempt; higher exposure to ads for pharmaceutical cessation aids was negatively associated with having made a quit attempt. There was a significant negative interaction between state- and Legacy-sponsored advertisements. CONCLUSIONS Exposure to state-sponsored advertisements was far below Centers for Disease Control and Prevention-recommended best practices. The significant negative relationships between antismoking advertising and adult smoking provide strong evidence that tobacco-control media campaigns help reduce adult smoking. The significant negative interaction between state- and Legacy-sponsored advertising suggests that the campaigns reinforce one another.

Explicit and Implicit Evaluation of Physician Adherence to Hypertension Guidelines

This study evaluated physician adherence to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) hypertension guidelines in 6 community‐based clinics. Explicit review of retrospective medical record data for patients with uncontrolled hypertension measured guideline adherence using 22 criteria. Mean overall guideline adherence was 53.5% and did not improve significantly over time. Random‐effects models demonstrated significant associations between guideline adherence and various demographic and medical predictors, including age, minority status, comorbid conditions, and number of medications. A subsequent implicit review evaluated the degree to which nonadherence was justifiable and identified factors that might have affected adherence. Nonadherence was rated as justifiable for only 6.6% of the failed explicit criteria. In general, adherence to the JNC 7 guidelines was modest even when barriers that might have affected adherence were taken into consideration.

A diabetes education multimedia program in the waiting room setting

IntroductionThis study evaluated the impact of a waiting room-administered, low-literacy, computer multimedia diabetes education program on patient self-management and provider intensification of therapy.MethodsIn this randomized, controlled trial, 129 participants either viewed a computer multimedia education program (intervention group) or read an educational brochure (control group) while in the waiting room. Participants were uninsured, primarily ethnic minority adults with type 2 diabetes receiving care from a county clinic in Chicago, Illinois. Wilcoxon test, t-test, and linear mixed model analyses evaluated changes in diabetes knowledge, self-efficacy, behaviors, medications prescribed, hemoglobin A1c (HbA1c), and blood pressure levels over 3 months.ResultsDuring the study period, there was an increase in the number of oral diabetes medications prescribed over three months to multimedia users compared with those in the control group (P=0.017). HbA1c declined by 1.5 in the multimedia group versus 0.8 in the control group (P=0.06). There were no differences between groups in changes in blood pressure levels, self-efficacy, and most diabetes-related behaviors. Self-reported exercise increased in the control group compared with the multimedia group (0.9 days/week vs. 0.1 days/week, P=0.016).ConclusionMultimedia users received a greater intensification of diabetes therapy, but demonstrated no difference in self-management in comparison with those receiving educational brochures. The availability of a computer multimedia program in the waiting room appears to be a novel and acceptable approach in providing diabetes education for underserved populations.

Logistic Regression With Multiple Random Effects: A Simulation Study of Estimation Methods and Statistical Packages

Several statistical packages are capable of estimating generalized linear mixed models and these packages provide one or more of three estimation methods: penalized quasi-likelihood, Laplace, and Gauss–Hermite. Many studies have investigated these methods’ performance for the mixed-effects logistic regression model. However, the authors focused on models with one or two random effects and assumed a simple covariance structure between them, which may not be realistic. When there are multiple correlated random effects in a model, the computation becomes intensive, and often an algorithm fails to converge. Moreover, in our analysis of smoking status and exposure to antitobacco advertisements, we have observed that when a model included multiple random effects, parameter estimates varied considerably from one statistical package to another even when using the same estimation method. This article presents a comprehensive review of the advantages and disadvantages of each estimation method. In addition, we compare the performances of the three methods across statistical packages via simulation, which involves two- and three-level logistic regression models with at least three correlated random effects. We apply our findings to a real dataset. Our results suggest that two packages—SAS GLIMMIX Laplace and SuperMix Gaussian quadrature—perform well in terms of accuracy, precision, convergence rates, and computing speed. We also discuss the strengths and weaknesses of the two packages in regard to sample sizes.

Electronic Cigarettes among Priority Populations: Role of Smoking Cessation and Tobacco Control Policies

INTRODUCTION The electronic cigarette (e-cigarette) market has evolved rapidly in recent years, with exploding growth in brands and product types; however, e-cigarette use among priority (sexual minority and low-income) populations and its relationship with smoking-cessation and tobacco control policies have yet to be fully characterized. METHODS The authors conducted a nationally representative online survey of 17,522 U.S. adults in 2013. Participants were drawn from GfKs KnowledgePanel. Logistic regression models were used to analyze relationships between e-cigarettes (awareness, ever use, current use) and cigarette smoking and cessation behaviors, tobacco control policies, and demographics. Analyses were conducted in 2014. RESULTS Approximately 15% of participants reported ever use of e-cigarettes, 5.1% reported current use, and 34.5% of ever users reported current use. E-cigarette awareness was lower among women, minorities, and those with low education. Ever and current use of e-cigarettes was higher among current cigarette smokers, young adults, and those with low SES; both ever use and current use were correlated with current cigarette smoking status, particularly when combined with quit intentions or attempts. Lesbian/gay/bisexual/transgender respondents had higher rates of ever use and current use. Ever use was lower in states with comprehensive smoking bans. No significant relationship between cigarette price and e-cigarette use was detected. CONCLUSIONS Ongoing surveillance of e-cigarette use among subpopulation groups and monitoring their use for combustible cigarette cessation are needed. Important variations in the patterns and correlates of e-cigarette awareness and use exist among priority populations. These findings have implications for future e-cigarette policy decisions.

Garbage in, Garbage Out: Data Collection, Quality Assessment and Reporting Standards for Social Media Data Use in Health Research, Infodemiology and Digital Disease Detection

Background Social media have transformed the communications landscape. People increasingly obtain news and health information online and via social media. Social media platforms also serve as novel sources of rich observational data for health research (including infodemiology, infoveillance, and digital disease detection detection). While the number of studies using social data is growing rapidly, very few of these studies transparently outline their methods for collecting, filtering, and reporting those data. Keywords and search filters applied to social data form the lens through which researchers may observe what and how people communicate about a given topic. Without a properly focused lens, research conclusions may be biased or misleading. Standards of reporting data sources and quality are needed so that data scientists and consumers of social media research can evaluate and compare methods and findings across studies. Objective We aimed to develop and apply a framework of social media data collection and quality assessment and to propose a reporting standard, which researchers and reviewers may use to evaluate and compare the quality of social data across studies. Methods We propose a conceptual framework consisting of three major steps in collecting social media data: develop, apply, and validate search filters. This framework is based on two criteria: retrieval precision (how much of retrieved data is relevant) and retrieval recall (how much of the relevant data is retrieved). We then discuss two conditions that estimation of retrieval precision and recall rely on—accurate human coding and full data collection—and how to calculate these statistics in cases that deviate from the two ideal conditions. We then apply the framework on a real-world example using approximately 4 million tobacco-related tweets collected from the Twitter firehose. Results We developed and applied a search filter to retrieve e-cigarette–related tweets from the archive based on three keyword categories: devices, brands, and behavior. The search filter retrieved 82,205 e-cigarette–related tweets from the archive and was validated. Retrieval precision was calculated above 95% in all cases. Retrieval recall was 86% assuming ideal conditions (no human coding errors and full data collection), 75% when unretrieved messages could not be archived, 86% assuming no false negative errors by coders, and 93% allowing both false negative and false positive errors by human coders. Conclusions This paper sets forth a conceptual framework for the filtering and quality evaluation of social data that addresses several common challenges and moves toward establishing a standard of reporting social data. Researchers should clearly delineate data sources, how data were accessed and collected, and the search filter building process and how retrieval precision and recall were calculated. The proposed framework can be adapted to other public social media platforms.

The 18-Month Impact of Special Supplemental Nutrition Program for Women, Infants, and Children Food Package Revisions on Diets of Recipient Families

BACKGROUND Beginning in 2009, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) revised its food packages and provided more whole grains, fruits, and vegetables and fewer foods with high saturated fat content. However, knowledge of the impact of this policy shift on the diets of WIC participants remains limited. PURPOSE To examine the longer-term impact of the 2009 WIC food package change on nutrient and food group intake and overall diet quality among African American and Hispanic WIC child participants and their mothers/caregivers. METHODS In this natural experiment, 24-hour dietary recalls were collected in the summer of 2009, immediately before WIC food package revisions occurred in Chicago IL and at 18 months following the food package change (winter/spring 2011). Generalized estimating equation models were used to compare dietary intake at these two time points. Data were analyzed in July 2013. RESULTS Eighteen months following the WIC food package revisions, significant decreases in total fat (p=0.002) and saturated fat (p=0.0004) and increases in dietary fiber (p=0.03) and overall diet quality (p=0.02) were observed among Hispanic children only. No significant changes in nutrient intake or diet quality were observed for any other group. The prevalence of reduced-fat milk intake significantly increased for African American and Hispanic children, whereas the prevalence of whole milk intake significantly decreased for all groups. CONCLUSIONS Positive dietary changes were observed at 18 months post policy implementation, with the effects most pronounced among Hispanic children.

Evaluation of effectiveness of a facet wiring technique: Anin vitro biomechanical investigation

The effects of facet wiring procedure commonly used for stabilizing cervical spines after laminectomy or bilateral facet dislocation on the motion behavior of whole cervical spines are investigated using a Selspot II® system. A fresh human ligamentous intact specimen was potted at T1/T2 vertebra and clinically relevant loads applied to the topmost vertebra (C2) of the specimen. The resulting three rotational components of each of the five vertebral bodies (C3-C7) were recorded. Specimen was injured to mimic total laminectomies at C5 and C6 vertebral levels and tested again. The injured specimen was stabilized, using a facet wiring construct, across C4-C7 segment before testing for the final time. The injured specimens, compared to the intact specimens, demonstrated an increase in flexion-extension of about 10%. Facet wiring imparted stability to the cervical spine by stiffening segments up to roughly four times intact values.

Price-related promotions for tobacco products on Twitter

Objectives This cross-sectional study examined price-related promotions for tobacco products on Twitter. Methods Through the Twitter Firehose, we obtained access to all public tweets posted between 6 December 2012 and 20 June 2013 that contained a keyword suggesting a tobacco-related product or behaviour (eg, cigarette, vaping) in addition to a keyword suggesting a price promotion (eg, coupon, discount). From this data set of 155 249 tweets, we constructed a stratified sampling frame based on the price-related keywords and randomly sampled 5000 tweets (3.2%). Tweets were coded for product type and promotion type. Non-English tweets and tweets unrelated to a tobacco or cessation price promotion were excluded, leaving an analytic sample of 2847 tweets. Results The majority of tweets (97.0%) mentioned tobacco products while 3% mentioned tobacco cessation products. E-cigarettes were the most frequently mentioned product (90.1%), followed by cigarettes (5.4%). The most common type of price promotion mentioned across all products was a discount. About a third of all e-cigarette-related tweets included a discount code. Banned or restricted price promotions comprised about 3% of cigarette-related tweets. Conclusions This study demonstrates that the vast majority of tweets offering price promotions focus on e-cigarettes. Future studies should examine the extent to which Twitter users, particularly youth, notice or engage with these price promotion tweets.