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Background We evaluated the effectiveness of implementing a proficiency-driven, simulation-based knot tying and suturing curriculum for medical students during their 3rd-year surgery clerkship. Methods Medical students on the 3rd-year surgical clerkship completed a proficiency-driven, simulation-based knot tying and suturing curriculum consisting of 6 tasks. The effectiveness was evaluated by comparing the initial presession scores to the final postsession scores on an 8-item self-efficacy scale and evaluating pass rates on end of clerkship skills testing. A paired t test was used to analyze data. Results Sixty-five students had matched preintervention and postintervention questionnaires for analysis. Pass rates approached 100% by the 3rd attempt on all tasks. Significant gains on all 8 items of the self-efficacy questionnaire from pretraining to post-training were noted. Timing of the general surgery rotation did not impact results. Conclusions Implementation of a simulation-based training, proficiency-driven knot tying and suturing curriculum for 3rd-year medical students during the surgery clerkship is feasible and effective in improving student self-efficacy and objective proficiency toward performance of the tasks taught.

Background The aim of this study was to assess one-year implant survival after lateral window sinus augmentation using PRGF combined with various bone grafting materials. Material and Methods This was a retrospective chart review and radiographic analysis of patients that had undergone lateral window sinus augmentation with PRGF and had dental implants placed at least 6 months post augmentation. All implants included were followed up for at least one year after placement. Demographic, sinus and implant related characteristics (residual ridge height, sinus membrane perforation, type of graft material, implant length and width and ISQ at placement) were analyzed. Results A total of 31 patients with 39 sinus augmentations and 48 implants were included. The mean follow up was 22.8 ± 9.9 months. Implant survival was 95.8%, with 2 implants overall failing. Among all the variables assessed, the only one found to be associated with an increased risk for implant failure was the use of xenograft as bone grafting material in the sinus. Conclusions Within the limitations of this study, dental implants placed in maxillary sinuses grafted with PRGF in combination with bone grafting materials, exhibit high implant survival rates after at least one year follow up. Key words:PRGF, sinus graft, growth factors, implant survival, platelet concentrates.

Key Points Question What is the increase in the colorectal cancer incidence rate from 49 to 50 years of age when large segments of the population begin average-risk screening? Findings This cross-sectional analysis of colorectal cancer incidence rates in 1-year age increments (30-60 years) from 2000 to 2015 in the Surveillance, Epidemiology, and End Results 18 registries found an incidence rate increase of 46.1% from 49 to 50 years of age. A total of 92.9% of the cases of colorectal cancer diagnosed at 50 years of age were invasive (beyond in situ stage). Meaning Steep incidence increases from 49 to 50 years of age are consistent with preexisting colorectal cancers diagnosed via screening uptake, supporting the presence of a large undetected preclinical case burden in patients younger than 50 years that is not reflected in observed Surveillance, Epidemiology, and End Results incidence rates., Importance Early-onset colorectal cancer incidence rates among patients aged 45 to 49 years have been considered much lower compared with the rates among patients aged 50 to 54 years, prompting debate about earlier screening benefits at 45 years. However, the observed incidence rates in the Surveillance, Epidemiology, and End Results (SEER) registries may underestimate colorectal cancer case burdens in those younger than 50 years compared with those older than 50 years because average-risk screening is generally not performed to detect preclinical cases of colorectal cancer. Finding steep incidence increases of invasive stage (beyond in situ) cases of colorectal cancer from age 49 to 50 years would be consistent with high rates of preexisting, undetected cancers in younger patients ultimately receiving a diagnosis of colorectal cancer after undergoing screening at 50 years. Objective To assess the preclinical burden of colorectal cancer by analyzing its incidence in 1-year age increments, focusing on the transition between ages 49 and 50 years. Design, Setting, and Participants Data from the SEER 18 registries, representing 28% of the US population, were used to conduct a cross-sectional study of colorectal cancer incidence rates from January 1, 2000, to December 31, 2015, in 1-year age increments (ages 30-60 years) stratified by US region (South, West, Northeast, and Midwest), sex, race, disease stage, and tumor location. Statistical analysis was conducted from November 1, 2018, to December 15, 2019. Main Outcomes and Measures Incidence rates of colorectal cancer. Results A total of 170 434 cases of colorectal cancer were analyzed among 165 160 patients (92 247 men [55.9%]; mean [SD] age, 51.6 [6.7] years). Steep increases in the incidence of colorectal cancer in the SEER 18 registries were found from 49 to 50 years of age (46.1% increase: 34.9 [95% CI, 34.1-35.8] to 51.0 [95% CI, 50.0-52.1] per 100 000 population). Steep rate increases from 49 to 50 years of age were also seen in all US regions, men and women, white and black populations, and in colon and rectal cancers. The rate ratio incidence increase in the SEER 18 registries from 49 to 50 years of age (1.46 [95% CI, 1.43-1.51]) was significantly higher than earlier 1-year age transitions. Steep rate increases in the SEER 18 registries were found from 49 to 50 years of age in localized-stage (75.9% increase: 11.2 [95% CI, 10.7-11.7] to 19.7 [95% CI, 19.0-20.3] per 100 000) and regional-stage (30.3% increase: 13.2 [95% CI, 12.7-13.8] to 17.2 [95% CI, 16.7-17.8] per 100 000) colorectal cancers. A total of 8799 of the 9474 cases (92.9%) of colorectal cancer in the SEER 18 registries from 2000 to 2015 that were diagnosed among individuals aged 50 years were invasive. Conclusions and Relevance Steep incidence increases between 49 and 50 years of age are consistent with previously undetected colorectal cancers diagnosed via screening uptake at 50 years. These cancers are not reflected in observed rates of colorectal cancer in the SEER registries among individuals younger than 50 years. Hence, using observed incidence rates from 45 to 49 years of age alone to assess potential outcomes of earlier screening may underestimate cancer prevention benefits., This cross-sectional study uses data from the Surveillance, Epidemiology, and End Results registries to assess the preclinical burden of colorectal cancer by analyzing its incidence in 1-year age increments, focusing on the transition between 49 and 50 years of age.

Introduction Quitting smoking has been proven to benefit smokers with diabetes. However, among older patients with diabetes, the evidence regarding an association between smoking status and the risk of type 2 diabetes mellitus-related emergency department (ED) visits has not been well investigated. Methods A retrospective cohort study was performed by using the Louisiana State University Health Care Services Division electronic health records from 2009 to 2011. Patients aged 65 years or older with type 2 diabetes and smoking status recorded at least twice in 2010 were selected. Selected patients with diabetes were classified into nonsmokers, former smokers, continuing smokers, and relapsed smokers. Cox proportional hazards regression models were used to estimate the adjusted hazard ratio (aHR) of 1-year type 2 diabetes-related ED visits for each group compared with nonsmokers. Results There were 174 (8.2%) continuing smokers and 77 (3.6%) relapsed smokers in 2,114 patients with diabetes who were studied. Rates of type 2 diabetes-related ED visits were highest in relapsed smokers (28.6%). Compared with nonsmokers, relapsed smokers had a significantly higher risk of type 2 diabetes-related ED visits (aHR = 1.62; 95% confidence interval [CI], 1.04-2.50). After stratifying by sex, a significantly increased risk of type 2 diabetes-related ED visits was shown only in male relapsed smokers (aHR = 2.05; 95% CI, 1.13-3.71) and female continuing smokers (aHR = 1.65; 95% CI, 1.10-2.47) compared with nonsmokers. Conclusion Older men with diabetes who were relapsed smokers had a higher risk of type 2 diabetes-related ED visits. Future research and clinical practice should focus on these patients and create more effective interventions for smoking cessation and diabetes management.

PURPOSE: To examine (1) the trend and associated factors of Oncotype DX (ODX) use among hormone receptor-positive (HR+) breast cancer (BC) patients in 2004–2015; (2) the trend of reported chemotherapy by Recurrence Score (RS); and (3) the survival differences associated with ODX use. METHODS: ODX data from Genomic Health Inc. were linked with 17 SEER registries data. HR + BC cases with lymph node negative (N0) or 1–3 positive LNs (N1) from 2004–2015 were analyzed. The Cochrane-Armitage trend test, logistic regression, Kaplan–Meier survival curve, and stratified Cox model were performed. Survival analysis was restricted to HR+/HER2− patients from 2010 to 2014, matched on propensity score. RESULTS: ODX use increased substantially from 2004 to 2015 (N0: 2.0% to 42.7%; N1: 0.3% to 27.9%). Non-Hispanic black and Medicaid insured patients had lower odds of receiving ODX. N0 patients with moderately differentiated or 2.1–5.0 cm tumor and N1 patients with well-differentiated or < 2.0 cm tumor had higher odds of using ODX. The reported chemotherapy use decreased significantly with low and intermediate RS, and increased for high RS among N0 patients. ODX use was associated with better breast cancer-specific survival [hazard ratio (95% CI) N0 1.96 (1.60–2.41), N1 1.90 (1.42–2.54)] and overall survival [N0 2.06 (1.83–2.31), N1 1.72 (1.42–2.09)], especially in the first 36 months. CONCLUSION: ODX use has increased significantly since 2004, nonetheless disparities remain, especially for racial/ethnic minorities and Medicaid insured patients. Administering chemotherapy based on ODX results has been improved among N0 patients. Patients receiving ODX had better survival than those not.

Summary Aim This study sought to determine whether a clinically acceptable shear bond strength (SBS) of metal orthodontic brackets is achievable to CAD/CAM (Computer-Aided Design/Manufacturing) lithium silicate infused with zirconia and whether a chemical pre-treatment bonding protocol produced a higher shear bond strength. Materials and methods Twenty lithium silicate infused with zirconia (CELTRA® DUO) samples, twenty zirconia samples, and twenty lithium disilicate samples were fabricated to replicate the facial surface of a mandibular left first molar. The samples were split into two test groups, one of which received a chemical pre-treatment protocol (hydrofluoric acid etch). Shear bond strength testing was conducted and the mean, maximum, minimal, and standard deviation SBS values for each were calculated and recorded in MPa. An Adhesive Resin Index (ARI) score was also assigned to each sample to assess the mode of bond failure. Results SBS of the lithium silicate infused with zirconia groups were significantly less than the chemically pre-treated lithium disilicate group, however both materials, when chemical pre-treatment protocol was used, were not statistically different than the enamel control. Conclusions Orthodontic bonding to lithium silicate infused with zirconia yielded a weaker shear bond strength than bonding to traditional lithium disilicate, however, when the surface was pre-treated with hydrofluoric acid etch it provides a bond strength that is within an acceptable clinical range.

BACKGROUND Facial cellulitis of odontogenic origin (FCOO) can lead to systemic complications in children. Research on factors leading to improvement of outcomes is limited. AIM The aim of this study was to investigate patient characteristics, treatment modalities (antibiotics and route of administration), length of stay in the hospital, time till definitive treatment, and factors related to early treatment of FCOO. DESIGN A retrospective review was performed to identify children presenting to the emergency department of a paediatric hospital with FCOO over a 5-year period. Data were extracted from records of included patients. RESULTS Sixty-four records were included for analysis with mean age of 8.19 ± 4.5 years. Significantly more patients received clindamycin (79.7%) than penicillin-based antibiotic (18.8%) with P

Objective: The objective of this study was to formulate experimental orthodontic bracket adhesives and test their mechanical properties, fluoride release and antibacterial activity. Methods: Four experimental antibacterial orthodontic bracket adhesives were prepared with different compositions of synthesized antibacterial monomers replacing total 5% of dental monomers in the control Transbond XT (3M): 5%C11, 3.5%C11+1.5%C2, 5%C16, and 3.5%C16+1.5%C2. Transbond XT alone was used as control. These groups were used to bond premolar brackets to extracted premolars. Shear bond strength (SBS) was tested using an Instron machine. For antibacterial test, disk specimens (10mm diameter, 1mm thick, n=4) were fabricated and incubated with cultures of cariogenic Streptococcus mutans for 48h, and following gentle sonication, S. mutans biofilms in colony-forming-units (CFU) on the disks were enumerated by plating on agar medium. The data were analyzed using ANOVA and Tukey test (α=0.05). Results: All experimental groups had similar shear bond strength (no significant difference) to the control. All experimental groups showed significant inhibitory effect against S. mutans biofilm formation, when compared to the control, but there was no significant difference between experimental groups. Conclusion: Antibacterial orthodontic adhesive can be fabricated to have similar mechanical properties but better caries-inhibitory effect than current adhesive. RESUMO Objetivo: o objetivo do presente estudo foi formular, experimentalmente, adesivos para colagem de braquetes ortodônticos e testar as suas propriedades mecânicas, sua liberação de flúor e sua atividade antibacteriana. Métodos: quatro adesivos ortodônticos antibacterianos foram preparados experimentalmente usando monômeros sintéticos antibacterianos com diferentes composições, substituindo-se 5% do monômero do grupo controle (Transbond XT, 3M) por: 5%C11; 3,5%C11 + 1,5%C2; 5%C16; ou 3,5%C16 + 1,5%C2. O Transbond XT original foi utilizado como controle. Esses diferentes adesivos foram usados para colar braquetes de pré-molares em pré-molares extraídos. A resistência da colagem ao cisalhamento (RCC) foi testada utilizando-se uma máquina Instron. Para os testes antibacterianos, amostras em formato de disco (10 mm de diâmetro, 1 mm de espessura, n = 4) foram fabricadas e incubadas por 48 horas com culturas cariogênicas de Streptococcus mutans. Após leve sonicação, os discos contendo os biofilmes de S. mutans em unidades formadoras de colônia (UFC) foram colocados em placas com meio de cultura ágar e numerados. Os dados foram analisados utilizando-se ANOVA e teste de Tukey (α?#8197;= 0,05). Resultados: todos os grupos experimentais apresentaram RCC semelhante (sem diferença significativa) ao grupo controle. Todos os grupos experimentais apresentaram significativo efeito inibitório contra a formação do biofilme de S. mutans, em comparação ao grupo controle, porém sem diferença significativa entre os grupos experimentais. Conclusão: adesivos ortodônticos antibacterianos podem ser produzidos para alcançar propriedades mecânicas semelhantes às dos adesivos atuais, porém com melhores efeitos inibitórios de cáries.

Summary Objective The aim of this study was to determine if there are differences between the shear bond strengths of 3 types of ceramic brackets when bonded to different ceramic substrates using an aluminium oxide air abrasion etchant protocol. Materials and methods Substrate groups consisting of thirty-six lithium disilicate (e.max® CAD) samples and thirty-six lithium silicate infused with zirconia (CELTRA® DUO) samples were fabricated to replicate the facial surface of a left maxillary central incisor. The surface of all samples was prepared with an aluminium oxide air abrasion etchant protocol. Each substrate group was split into three test groups (n = 12). Each test group was bonded using a different brand of ceramic orthodontic bracket. Shear bond strength (SBS) testing was conducted and the mean SBS values for each group were calculated and recorded in MPa. An Adhesive Resin Index (ARI) score was also assigned to each sample to assess the location of bond failure. Results Mean SBS of the e.max® CAD groups were significantly less than the CELTRA® DUO groups. Symetri brackets showed significantly higher shear bond strengths to both substrates than both of the other brackets tested. ARI scores of the e.max® CAD groups were significantly less than the CELTRA® DUO groups. Conclusion The Symetri bracket was the only bracket that was effective for both substrates (mean SBS > 6 mPa). The Etch Master protocol does not appear effective for e.max® CAD.

To synthesize a small library of antibacterial dental monomers based on quaternary ammonium salts and to test their antibacterial activity against cariogenic bacteria.Five new antibacterial monomers were synthesized and characterized by NMR, IR and HRMS.Cytotoxicity assays using human gingival fibroblast cells showed that these new antibacterial monomers were biocompatible at concentrations of 10⁻⁵ M and displayed less cytotoxicity than BisGMA, a common dental monomer. When analyzed in vitro, all new monomers demonstrated strong inhibitory activity against biofilm formation by cariogenic Streptococcus mutans and Lactobacillus casei. Results indicated that antibacterial monomers containing a long alkyl (i.e. hexadecyl) chain are superior to their shorter-chain counterparts. The cross-linking monomers based on glycerol dimethacrylate also consistently outperformed their monomethacrylate analogs. Finally, the ammonium salts containing the dimethylbenzyl moiety were superior to the similar structures containing 1,4-diazabicyclo[2.2.2]octane (DABCO) in some cases.All five new monomers were deemed biocompatible at concentrations of 10⁻⁵ M or less, and most had better biocompatibility than BisGMA. Dimethacrylate monomers 5 and 6 generally demonstrated high antibacterial activities, with the highest activity shown for the most lipophilic monomer 6, and these new antibacterial monomers have potential future application in dental composites and bonding agents.

Background and objectives: Smoking is associated with a lower health-related quality of life (HRQOL). However, there is little information about the association between HRQOL in relation to race, income, and smoking status. The present study aimed to assess the association between HRQOL and smoking status for those of different races and income levels. Materials and Methods: This study applied a cross-sectional design using data from the 2017 patient survey of the Louisiana Tobacco Control Initiative. We obtained 1108 responses from patients at eight Louisiana public hospitals. The EuroQol (EQ-5D) US index score assessed HRQOL. Smoking status was classified into four groups: never smoked, former smoker, current smoker with a quit attempt, and current smoker without a quit attempt. Multivariate linear regression analyses were used to estimate the HRQOL for black or African Americans and whites. Results: The patients were predominantly black or African American (58.9%) with lower-income (71.2%). Bivariate analyses showed that there were differences in income levels between black or African Americans and whites (p = 0.006). Moreover, black or African Americans (median = 0.80) had a higher mean of HRQOL than whites (median = 0.76). Among lower-income black or African Americans, current smokers with a quit attempt had a lower HRQOL than current smokers (coefficient = &minus, 0.12, p &lt, 0.01). Conclusions: Racial and income disparities were evident with regards to HRQOL, with lower-income black or African Americans who were current smokers with a quit attempt having a lower HRQOL. Intervention programs for smoking cessation should target lower-income black or African American smokers who have a prior quit attempt and provide effective cessation services to help them quit smoking and improve their HRQOL.

Introduction: Tobacco use, which is directly responsible for 10% of total deaths per year globally, remains consistently high, with approximately 20% of the population reporting regular consumption globally. Moreover, health disparities regarding tobacco consumption and smoking cessation are growing between rural and urban populations worldwide. Social media interventions for tobacco cessation may effectively reach both groups. The objective of this study was to evaluate the efficacy of a WeChat-delivered smoking cessation intervention among rural and urban Chinese smokers, and to assess moderating variables that may contribute to differential intervention efficacy. Methods: WeChat was used to recruit smokers into this intervention study between 1 July and 5 August 2019. Participants were randomized to one of three intervention schedules: participants in the Standard Group and the Enhanced Group received 20 smoking-related messages over 2 weeks, whereas participants in the Enhanced Group received an extra 6 oral health-related messages for one week. Participants in the control group received 20 smoking-related messages after the post-intervention assessment. Participants completed questionnaires at baseline and at 4 weeks follow-up. Our primary outcome was smoking cessation stage of change and secondary outcome was 24-h point prevalence abstinence (PPA). Urban and rural areas were based on self-reported living areas. Chi-squared test, Fisher’s exact test, ANOVA test, linear regression, and logistic regression were used for analysis. Results: Overall, 403 participants completed the intervention (233 rural, 107 suburban, 63 urban). Compared to urban participants, rural participants were more likely to have progressed to a later stage of change (β = 0.40, 95% CI: 0.13, 0.67) and to report higher 24-h PPA rates at follow-up (aOR = 3.23, 95% CI: 1.36, 7.68). After stratification by living area, the intervention effects in stage of change and 24-h PPA rate at follow-up were only found in the urban subgroup. Discussion: Smokers who lived in rural areas reported better smoking cessation outcomes compared with urban smokers, however, the efficacy of a WeChat-based smoking cessation intervention was only found for participants living in an urban area. WeChat based smoking cessation interventions should be used to promote smoking cessation in urban, suburban, and rural areas.

Study Objective The adolescent pregnancy rate in Louisiana (LA) and Mississippi (MS) is one of the highest in the United States. One approach to decrease that rate is to increase contraceptive use. We sought to characterize LA and MS family physicians' (FPs) contraception counseling for adolescents with a focus on the intrauterine contraceptive device (IUD). Design, Setting, Participants, Interventions, and Main Outcome Measures Online survey of resident and practicing physician members of the LA and MS Academy of FPs. Results Three hundred ninety-eight of 1616 invited FPs responded; 244 were included in our analysis. When counseling adolescents about contraception, respondents “frequently discussed” oral contraceptives and condoms 87.5% (210/240) and 83.8% (202/241) of the time, respectively. Newer and more highly effective contraceptives such as the ring, patch, IUD, and implant were “frequently discussed” only 34.6% (82/237)-39.3% (92/234) of the time. In the previous 6 months, 56% (136/243) of respondents ever discussed an IUD with an adolescent. Respondents were more likely to have discussed IUDs if they learned IUD insertion during residency, had on-site access to IUD inserters, believed they were competent and/or comfortable with IUD counseling. In 5 clinical scenarios asking whether the respondent would recommend an IUD to a 17- or a 27-year-old patient (in all scenarios patients were eligible for an IUD), respondents were restrictive overall and significantly fewer would recommend an IUD for the adolescent. Conclusion Our results suggest that there are missed opportunities for full-scope contraception counseling by LA and MS FPs. When these FPs counsel adolescents about contraception they less frequently discuss newer methods and more highly effective methods. Additionally many LA and MS FPs use overly restrictive eligibility criteria when considering IUDs.

Introduction: Triple-negative breast cancer (TNBC) is an aggressive, heterogeneous subtype of breast cancer. TNBC patients have generally high risk of recurrence and metastasis, and treatment options remain limited, as there are no effective targeted therapies available. In USA, TNBC is diagnosed disproportionately more frequently in African American (AA) women than in European American (EA) women. We set out to investigate the role of social determinants in racial disparities in TNBC. Methods: TNBC patients diagnosed in Louisiana from 2010-2012 were identified from the Louisiana Tumor Registry. Patients were geocoded to census tract of residence at time of diagnosis. Census tract population and socioeconomic measures were obtained from the US Census American Community Survey. We used multilevel statistical models to analyze the role of neighborhood concentrated disadvantage index (CDI), a robust measure of physical and social environment, in racial disparities in TNBC incidence, stage at diagnosis, and stage-specific survival for the study population. CDI scores were calculated according to the PhenX Toolkit protocol. Results: We identified 1,216 women with TNBC for the study. Controlling for age, we found that AA women had a 2.21-fold risk of TNBC incidence compared to EA in Louisiana. Results from multivariate analyses indicated that the incidence of TNBC was independent of neighborhood CDI, as was the racial disparity. However, CDI did explain existing racial disparities in both stage at diagnosis and stage-specific survival. The odds of diagnosis at later stages were 42% higher for black women. A single standard deviation increase in CDI increased the hazard of breast cancer-related death by 19%. Overall, our results suggest that the increased incidence of TNBC in black women is independent of CDI, while neighborhood environment has a greater impact than race on the promotion and progression of the disease. The socioeconomic disadvantage experienced by black women coupled with increased biologic risk for TNBC contribute to the large racial disparity in breast cancer mortality in Louisiana. Further research is needed to determine the mechanisms through which social determinants affect the promotion and progression of this disease and guide efforts to improve overall survival. Citation Format: Fokhrul Hossain, Denise Danos, Aubrey Gilliland, Claudia Leonardi, Tekeda Ferguson, Neal Simonsen, Qingzhao Yu, Om Prakesh, Richard Scribner, Lucio Miele. Social determinants of health disparities in triple-negative breast cancer in Louisiana [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C070.

Health disparities research increasingly relies on a social determinants of health approach, which focuses on identifying modifiable social and environmental factors that adversely affect health outcomes to create health disparities. We have used a multilevel framework that leverages cancer registry and US census data to examine the role of neighborhood social determinants in cancer incidence and survival in Louisiana. Multilevel studies of cases of colorectal, liver, and breast cancer reveal that differential exposure to unfavorable social and physical environments do contribute to racial disparities in cancer. In particular, we have observed that concentrated disadvantage, a robust measure of neighborhood environment, was positively associated with the incidence of colorectal cancer and hepatocellular carcinoma but not triple-negative breast cancer. Citation Format: Richard Scribner, Denise Danos, Claudia Leonardi, Tekeda Ferguson, Qingzhao Yu, Neal Simonsen, Xiao-Cheng Wu. Exploring social determinants of cancer outcomes using multilevel spatial analysis [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr IA08.

Mediation effect refers to the effect conveyed by a third variable, the mediator, to an observed relationship between an exposure and a response variable of interest. Mediation analysis is used widely in fields such as social science, prevention study, behavior research, and epidemiology. For example, it has been well established that low socioeconomic status is associated with poor health status. To reduce this health disparity, investigators would need to quantify the effects, called mediation effects, from different risk factors that intervene in the relationship between the socioeconomic status and health outcomes, so that efficient interventions can be carried out. The general multiple mediation analysis method, proposed by Yu et al., improved traditional methods (e.g., estimation of natural and controlled direct effects) to enable consideration of multiple mediators simultaneously and the use of linear and nonlinear predictive models for estimating mediation effects. A big data set includes a large number of variables. Within big data mediation analysis, the number of potential mediators is big. For example, in explaining the racial disparity in breast cancer survival, there are a lot of risk factors that need to be considered such as individual behaviors, environmental factors, social-economic status, treatment effects, diagnosis characters, and even gene expression variables. In this study, we propose to use a regularized mediation analysis method that identifies significant mediators and estimates their indirect effects simultaneously. Breast cancer is the most common cancer and the second leading cause of cancer death among women of all races. Despite the improvement of survival rates of breast cancer in the U.S., a significant difference between white and black women remains. Due to limitations of current analytic methods and the lack of comprehensive data sets, researchers have not been able to differentiate the relative effect that each factor contributes to the overall racial disparity. We use the CDC-funded Patterns of Care study and Enhancing Cancer Registry Data for Comparative Effectiveness Research study to examine the determinants of racial disparities in breast cancer survival using the propose regularized multiple mediation analysis. Using the proposed method, we identified important factors that explain the racial disparity in breast cancer survival, which includes the cancer stage-related variables (stage, tumor size, lymph nodes involvement, extension, and tumor size), molecular subtype, treatment methods such as surgery and hormonal therapy, and tumor grade. Age also contributed to the racial differences, but in an opposite direction. Black patients are more likely to be diagnosed at a younger age, which is related with better survival outcomes. Overall, we found that all racial disparity in survival among Louisiana breast cancer patients was explained by factors included in the study. Citation Format: Qingzhao Yu, Lu Zhang, Meichin Hsieh, Xiaocheng Wu, Richard A Scribner, Bin Li. Regularized multiple mediation analysis for big data set—With an application to explore racial disparity in breast cancer survival [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C020.

High-fidelity simulation-based training is used increasingly for prelicensure student teams. Such sessions rely on faculty who are able to provide quality prebriefing and debriefing to foster learning among participants. We investigated how well faculty conducted prebriefing and debriefing as part of high-fidelity simulation-based training for interprofessional education.Two trained observers independently rated 38 video-recorded sessions of combinations of 4 faculty conducting prebriefings and debriefings of prelicensure student teams after high-fidelity simulation-based training. Assessment was undertaken using the Objective Structured Assessment of Debriefing, an 8-item tool using a 5-point Likert scale (1 as minimum and 5 as maximum). Mean scores for each item were calculated. Inter-rater agreement was determined using Cohen's kappa. A one-way between-subjects analysis of variance with post-hoc Tukey's studentized range procedure was conducted to compare the effect of team facilitator grouping on the quality of team performance of each Objective Structured Assessment of Debriefing element during a prebriefing or a debriefing. Trend analyses of teams with 4 or more observations were performed using Kendall's Tau coefficient test and linear regression analyses to identify whether teams showed improvement through time. Statistical significance was set at P.05.A total of 7 combinations of faculty conducted between 1 to 14 prebriefings or debriefings. In general, faculty combinations performed better during debriefings compared with prebriefings, with only 1 team having 1 mean item score3.50. Statistically significant differences between faculty combinations in mean item scores was more pronounced during the prebriefings (2 of 3 Objective Structured Assessment of Debriefing items rated) than during debriefings (1 of 8 Objective Structured Assessment of Debriefing items rated). Effect sizes were strong for all differences. Linear regression analysis revealed a statistically significant change through time for the 3 rated prebriefing items and for 7 of the 8 rated debriefing items.Interprofessional faculty combinations in this study tended to have good quality prebriefings and debriefings. The quality of the prebriefings and debriefings can, however, be influenced by the composition of the facilitator teams, most prominently for prebriefings, and team performance does appear to change through time, especially during the debriefing. Future work will focus on whether the quality of prebriefings and debriefings influences learning by trainees.

There is increasing interest in Bayesian group sequential design because of its potential to improve efficiency in clinical trials, to shorten drug development time, and to enhance statistical inference precision without undermining the clinical trial’s integrity or validity. We propose a Bayesian sequential design for clinical trials with time-to-event outcomes and use alpha spending functions to control the overall Type I error rate. Bayes factor is adapted for decision-making at interim analyses. Algorithms are presented to make decision rules and to calculate power of the proposed tests. Sensitivity analysis is implemented to evaluate the impact of different choices of prior parameters on choosing critical values. The power of tests, the expected event size of the proposed design, and the quality of estimators are studied through simulations, and compared with the frequentist group sequential design. Simulations show that at fixed total number of events, the proposed design can achieve greater power and require smaller expected event size when appropriate priors are chosen, compared with the frequentist group sequential design. The feasibility of the proposed design is further illustrated on a real dataset. Supplementary materials for this article are available online.

Background: The dentist has a responsibility to provide nutritional counseling and fluoride consumption recommendations. The purpose of this study was to measure and compare the concentrations of fluoride in a large number of alternative milk beverages and bovine milk. Study design: Thirty-three milk alternatives, including 9 diverse types and 11 different brands, were analyzed using a fluoride ion-selective electrode (ISE) and an ISE meter. Fluoride concentrations were then compared among different types and between different brands. Results: Fluoride concentration ranged from 0.01 ppm (Malk® Pure Cashew Milk) to 0.80 ppm (Almond Breeze® Original Unsweetened Almond Milk) with a mean concentration of 0.32 ppm. When compared, bovine whole milk (0.03±0.00 ppm) was found to be significantly lower in fluoride than all samples analyzed except Malk Pure Cashew Milk, Soy Milk Vanilla, Rice Milk, and Pecan Milk. Major differences also existed between the same milk alternative types of different brands. Conclusion: The amount of fluoride varies among different types of milk alternatives and different brands. To ensure that the dental team can provide proper recommendations regarding fluoride use, manufacturers should consider placing fluoride concentrations on nutrition labels.

To determine whether high fidelity simulation-based training (SBT) of interprofessional teams involving trauma transfers has an immediate impact on participants' team-based attitudes and behaviors.A quasi-experimental, pre-/postintervention comparison design examined high fidelity SBT of inter-professional teams using a 2 scenario format with immediate after action structured debriefing. Pre-/postsession Readiness for Inter-Professional Learning Scale (RIPLS, 19 items, Likert-type) surveys as well as Interprofessional Teamwork (IPT, 15 items, Likert-type) questionnaires, and postscenario participant- and observer-rated Teamwork Assessment Scales (TAS, 3 subscales, 11 items, Likert-type) were completed during each training session. Mean RIPLS, IPT, and TAS scores were calculated and matched pre-/postscore differences compared using paired t-test or analysis of variance with Bonferroni adjustment.A large, urban, academic, state health sciences institution in the Southeastern United States during the 2014 to 2015 academic year.General surgery residents, emergency medicine residents, and senior undergraduate nursing students comprising ten interprofessional teams.From approximately 48 participants, matched pre-/postsession IPT surveys were available for 42 individuals; 45 had an observer TAS evaluation for both scenarios; and 40 completed TAS peer evaluations for both scenarios. 47 participants had matched RIPLS surveys. Statistically significant improvements in matched pre-/postscore differences occurred for all 15 IPT items. Observer TAS scores significantly improved on 2 of the 3 subscales comparing the second to the first scenario. Peer evaluations statistically improved comparing the second to the first scenario. Two of the 19 RIPLS items demonstrated statistically significant improvement.Interprofessional trauma team transfer training using SBT changes attitudes toward key team-based competencies and leads to learning them in the simulated environment. Such improvement in team-based skill and attitudes is an important first step in adopting team-based behaviors in the actual clinical environment and improving transfer care.

High-fidelity simulation (HFS) operating room (OR) inter-professional team training improves healthcare students' team-based attitudes and behaviours. Such improvements can diminish tribalism among the professions in the OR by overcoming entrenched perceptions of team members. We investigated whether simulation-based interprofessional student OR team training impacts students differently based on their professional background. From 2010 to 2013, HFS OR interprofessional student team training sessions were conducted involving senior medical students, senior undergraduate nursing students, and nurse anaesthesia students. The training involved a two-scenario format, each followed by a structured debriefing focusing on team-based competencies. Before and after each session, students completed a 15-item teamwork competencies self-efficacy survey as well as, from 2012-2013, the Readiness for Interprofessional Learning Scale (RIPLS). At the end of each session, they also completed a 6-item rating scale assessing overall team function during the session. Mean scores were calculated for each student professional group, post/pre mean differences were determined, and student t-test and ANOVA analyses were employed to compare within and between-group differences, respectively. Response rates were over 80% for each scale used. Medical students and undergraduate nursing students had significant improvements in team-based attitudes post- to pre-session. Medical students and nurse anaesthesia students had significant improvements in RIPLS scores. Statistically significant improvements from post- to pre-session were seen overall for both team-based attitudes (effect size = 0.83) and RIPLS (effect size = 0.37). The difference between the team-based scores between professions was significant; RIPLS differences were not. No significant difference existed between professions related to overall teamwork scores. HFS OR team training of healthcare students has beneficial but variable benefits for each professional group.

PURPOSE/OBJECTIVES In addition to an established peer mentoring programme, the Louisiana State University Health Sciences Center, School of Dentistry introduced a faculty-student mentoring programme, the first-year dental student (D1)-Faculty Guide Program, in 2013. The intent of the D1-Guide Program was to provide faculty mentorship for D1 students. The purpose of this study was to evaluate the outcomes of the programme and identify areas for improvement. METHODS Faculty members, D2 and D3 students were surveyed regarding their experiences and perceptions of the D1-Guide Program with a seven question and 12 question survey, respectively, via Survey Monkey® and data were analysed. RESULTS The response rate for the students and faculty was 61% and 64%, respectively. The majority of faculty (92%) felt comfortable serving as a guide to the D1 students with 79% of those surveyed having served as a guide for 3 or 4 years. The majority of students (81%) felt that the D1-Guide Program provided mentoring that was not redundant to existing peer mentoring and valuable to their acclimation to dental school. CONCLUSIONS Despite adding additional duties for faculty and students, the D1-Guide Program was considered valuable during the student's first year of dental school with encouragement to continue the programme. The programme helped establish a student-faculty rapport beyond the boundaries of the classroom.

Aim The objective of the present study was to determine which of six bonding protocols yielded a clinically acceptable shear bond strength (SBS) of metal orthodontic brackets to CAD/CAM lithium disilicate porcelain restorations. A secondary aim was to determine which bonding protocol produced the least surface damage at debond. Methods Sixty lithium disilicate samples were fabricated to replicate the facial surface of a mandibular first molar using a CEREC CAD/CAM machine. The samples were split into six test groups, each of which received different mechanical/chemical pretreatment protocols to roughen the porcelain surface prior to bonding a molar orthodontic attachment. Shear bond strength testing was conducted using an Instron machine. The mean, maximum, minimal, and standard deviation SBS values for each sample group including an enamel control were calculated. A t-test was used to evaluate the statistical significance between the groups. Results No significant differences were found in SBS values, with the exception of surface roughening with a green stone prior to HFA and silane treatment. This protocol yielded slightly higher bond strength which was statistically significant. Conclusion Chemical treatment alone with HFA/silane yielded SBS values within an acceptable clinical range to withstand forces applied by orthodontic treatment and potentially eliminates the need to mechanically roughen the ceramic surface.

We propose in this article a Bayesian sequential design using alpha spending functions to control the overall type I error in phase III clinical trials. We provide algorithms to calculate critical values, power, and sample sizes for the proposed design. Sensitivity analysis is implemented to check the effects from different prior distributions, and conservative priors are recommended. We compare the power and actual sample sizes of the proposed Bayesian sequential design with different alpha spending functions through simulations. We also compare the power of the proposed method with frequentist sequential design using the same alpha spending function. Simulations show that, at the same sample size, the proposed method provides larger power than the corresponding frequentist sequential design. It also has larger power than traditional Bayesian sequential design which sets equal critical values for all interim analyses. When compared with other alpha spending functions, O’Brien-Fleming alpha spending function has the largest power and is the most conservative in terms that at the same sample size, the null hypothesis is the least likely to be rejected at early stage of clinical trials. And finally, we show that adding a step of stop for futility in the Bayesian sequential design can reduce the overall type I error and reduce the actual sample sizes.

Introduction This study compared images displayed on 1 desktop monitor, 1 laptop monitor, and 2 tablets for the detection of contrast and working length interpretation, with a null hypothesis of no differences between the devices. Methods Three aluminum blocks, with milled circles of varying depth, were radiographed at various exposure levels to create 45 images of varying radiographic density. Six observers viewed the images on 4 devices: Lenovo M92z desktop (Lenovo, Beijing, China), Lenovo Z580 laptop (Lenovo), iPad 3 (Apple, Cupertino, CA), and iPad mini (Apple). Observers recorded the number of circles detected for each image, and a perceptibility curve was used to compare the devices. Additionally, 42 extracted teeth were imaged with working length files affixed at various levels (short, flush, and long) relative to the anatomic apex. Observers measured the distance from file tip to tooth apex on each device. The absolute mean measurement error was calculated for each image. Analysis of variance tests compared the devices. Observers repeated their sessions 1 month later to evaluate intraobserver reliability as measured with weighted kappa tests. Interclass correlation coefficients compared interobserver reliability. Results There was no significant difference in perceptibility detection between the Lenovo M92z desktop, iPad 3, and iPad mini. However, on average, all 3 were significantly better than the Lenovo Z580 laptop (P values ≤.015). No significant difference in the mean absolute error was noted for working length measurements among the 4 viewing devices (P = .3509). Conclusions Although all 4 viewing devices seemed comparable with regard to working length evaluation, the laptop computer screen had lower overall ability to perceive contrast differences.

PURPOSE: To investigate the impact of chemotherapy relative dose intensity (RDI) on cause-specific and overall survival for stage I–III breast cancer: estrogen receptor or progesterone receptor positive, human epidermal-growth factor receptor negative (ER+/PR+ and HER2−) vs. triple-negative (TNBC) and to identify the optimal RDI cut-off points in these two patient populations. METHODS: Data were collected by the Louisiana Tumor Registry for two CDC-funded projects. Women diagnosed with stage I–III ER+/PR+, HER2− breast cancer, or TNBC in 2011 with complete information on RDI were included. Five RDI cut-off points (95, 90, 85, 80, and 75%) were evaluated on cause-specific and overall survival, adjusting for multiple demographic variables, tumor characteristics, comorbidity, use of granulocyte-growth factor/cytokines, chemotherapy delay, chemotherapy regimens, and use of hormone therapy. Cox proportional hazards models and Kaplan–Meier survival curves were estimated and adjusted by stabilized inverse probability treatment weighting (IPTW) of propensity score. RESULTS: Of 494 ER+/PR+, HER2− patients and 180 TNBC patients, RDI < 85% accounted for 30.4 and 27.8%, respectively. Among ER+/PR+, HER2− patients, 85% was the only cut-off point at which the low RDI was significantly associated with worse overall survival (HR = 1.93; 95% CI 1.09–3.40). Among TNBC patients, 75% was the cut-off point at which the high RDI was associated with better cause-specific (HR = 2.64; 95% CI 1.09, 6.38) and overall survival (HR = 2.39; 95% CI 1.04–5.51). CONCLUSIONS: Higher RDI of chemotherapy is associated with better survival for ER+/PR+, HER2− patients and TNBC patients. To optimize survival benefits, RDI should be maintained ≥ 85% in ER+/PR+, HER2− patients, and ≥ 75% in TNBC patients.

To determine the impact of light curing of bonding agents on the microtensile bond strength (MTBS) of sealants on extracted teeth.Flat enamel surfaces were created on 54 extracted, sound human molars by sequential grinding. Three different sealants- Clinpro (3M ESPE), Ultraseal XT Hydro (Ultradent), and Fluorshield VLC (Dentsply)- were placed after acid etching without a bonding agent (control) or with three different bonding agents - Adper Single Bond Plus (3M ESPE), Peak Universal Bond (Ultradent), and PrimeBond Elect (Dentsply)- each in both light-cured and uncured form. The teeth were sectioned into bar specimens and the MTBS of each specimen was measured. The bond strength data were analyzed using two-way analysis of variance and Tukey's test (P=0.05).There was no significant difference between the MTBS of sealants in the thermocycled and non-thermocycled groups. The uncured adhesive had the lowest bond strength in each group, except for Clinpro after thermocycling. Teeth with uncured adhesive exhibited significantly lower bond strength in the Ultraseal (no thermocycling) and Fluroshield (with thermocycling) groups (P=0.02 and P=0.001, respectively).Adding bonding agents without curing before sealant placement weakened the microtensile bond strength. There was no significant difference in MTBS between the thermocycled and nonthermocycled groups.

Research shows aconsistent racial disparity in obesity between white and black adults in the United States. Accounting for the disparity is a challenge given the variety of the contributing factors, the nature of the association, and the multilevel relationships among the factors. We used the multivariable mediation analysis (MMA) method to explore the racial disparity in obesity considering not only the individual behavior but also geospatially derived environmental risk factors. Results from generalized linear models (GLM) were compared with those from multiple additive regression trees (MART) which allow for hierarchical data structure, and fitting of nonlinear and complex interactive relationships. As results, both individual and geographically defined factors contributed to the racial disparity in obesity. MART performed better than GLM models in that MART explained a larger proportion of the racial disparity in obesity. However, there remained disparities that cannot be explained by factors collected in this study.

ObjectiveIn surgery, dysfunctional teamwork is perpetuated by a ‘silo’ mentality modelled by students. Interprofessional education using high-fidelity simulation-based training (SBT) may counteract such modelling. We sought to determine whether SBT of interprofessional student teams (1) changes long-term teamwork attitudes and (2) is an effective form of team training.DesignA quasiexperimental, pre/postintervention comparison design was employed at an academic health sciences institution. High-fidelity simulation-based training of 42 interprofessional teams of third year surgery clerkship medical students and senior undergraduate nursing students was undertaken using a two-scenario format with immediate after action debriefing. Pre/postintervention TeamSTEPPS Teamwork Attitudes questionnaires (5 subscales, 30 items, Likert type) were given to the medical student and undergraduate nursing student classes. Pre/postsession Readiness for Inter-Professional Learning (RIPL; 19 items, Likert type) surveys and postscenario participant-rated and observer-rated Teamwork Assessment Scales (3 subscales, 11 items, Likert type) were given during each training session. Mean TeamSTEPPS Teamwork Attitudes Questionnaire, RIPL and Teamwork Assessment Scales scores were calculated; matched pre/postscore differences and trained versus non-trained TeamSTEPPS Teamwork Attitudes Questionnaire scores were compared using paired t-test or analysis of variance.ResultsBoth student groups had 10 significantly improved RIPL items as well as TeamSTEPPS Teamwork Attitudes Questionnaire (TTAQ) mutual support subscales. Medical students had a significantly improved TTAQ team structure subscale. Over a simulation-based training session, each observer-rated Teamwork Assessment Scales subscale and two self-rated Teamwork Assessment Scales subscales significantly improved. Trained students had significantly higher TTAQ team structure subscales than non-trained students.ConclusionsInterprofessional education using high-fidelity simulation-based training of students is effective at teaching teamwork, changing interprofessional attitudes and improving long-term teamwork attitudes.

Persistent postconcussion syndrome (PPCS) after mild traumatic brain injury (mTBI) is a significant public health and military problem for which there is limited treatment evidence. The aim of this study was to determine whether forty 150 kPa hyperbaric oxygen therapies (HBOTs) can improve symptoms and cognitive function in subjects with the PPCS of mTBI, using a randomized controlled crossover design with 2-month follow-up. Sixty-three civilian and military subjects with mTBI/PPCS were randomized to either 40 HBOTs at 150 kPa/60 minutes, once daily, 5 days per week in 8 weeks or an equivalent no-treatment control period. The Control Group was then crossed over to HBOT. Subjects underwent symptom, neuropsychological, and psychological testing, before and after treatment or control with retesting 2 months after the 40th HBOT. Fifty subjects completed the protocol with primary outcome testing. HBOT subjects experienced significant improvements in Neurobehavioral Symptom Inventory, Memory Index, Automated Neuropsychological Assessment Metrics, Hamilton Depression Scale, Hamilton Anxiety Scale, Post-Traumatic Stress Disorder Checklist, Pittsburgh Sleep Quality Index, and Quality Of Life after Brain Injury compared to the Control Group. After crossing over to HBOT the Control Group experienced near-identical significant improvements. Further improvements were experienced by both groups during the 2-month follow-up period. These data indicate that 40 HBOTs at 150 kPa/60 minutes demonstrated statistically significant improvements in postconcussion and Post-Traumatic Stress Disorder symptoms, memory, cognitive functions, depression, anxiety, sleep, and quality of life in civilian and military subjects with mTBI/PPCS compared to controls. Improvements persisted at least 2 months after the 40th HBOT. The study was registered on ClinicalTrials.gov (NCT02089594) on March 18, 2014 and with the U.S. Food and Drug Administration under Investigational New Drug #113823. The Institutional Review Boards of the United States Army Medical Research and Materiel Command Office of Research Protections Human Research Protection Office and the Louisiana State University School of Medicine (approval No. 7381) approved the study on May 13, 2014 and December 20, 2013, respectively.

Purpose: Radiation therapy has been found associated with increased risk of secondary bladder cancer diagnosis among prostate cancer patients. It is unknown whether this association varies by race. This study aimed to investigate whether the association between radiation and secondary bladder cancer differs for white vs. black prostate cancer patients. Methods: Data on white or black men who were diagnosed with primary localized prostate cancer in Louisiana between 2004 and 2013 and received radiation only or surgery only were obtained from Louisiana Tumor Registry. We excluded those who developed secondary bladder cancer within 180 days of the prostate cancer diagnosis or had follow-up less than 180 days or with unknown tumor size or Gleason score. Every patient was followed up until the end of 2016. The exposure variable was treatment (radiation only vs. surgery only). The outcome variable was the diagnosis of secondary bladder cancer and the time from prostate cancer diagnosis to secondary bladder cancer diagnosis or to loss to or end of follow-up. Covariates included age at diagnosis, marital status, insurance, census tract level poverty, tumor size, and Gleason score group. The competing risk survival analysis was applied. Death during follow-up was considered as competing event. Analysis was stratified by race. Results: Of 10,861 white and 5,117 black prostate cancer patients, 52.7% and 56.8% received only radiation respectively. Regardless of race, patients who only received surgery were younger, more likely to be married, privately insured, live in low poverty census tract, and have smaller or lower grade tumor (P Conclusions: Radiation is associated with increased risk of secondary bladder cancer among white prostate cancer patients, but not among black patients. Early screening of secondary bladder cancer need to be emphasized among white prostate cancer patients who received radiation therapy. Citation Format: Lu Zhang, Mei-Chin Hsieh, Qingzhao Yu, Xiao-Cheng Wu. Racial difference in the risk of secondary bladder cancer following radiation therapy among prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4204.

Clustering Lasso, a new regularization method for linear regressions is proposed in the paper. The Clustering Lasso can select variable while keeping the correlation structures among variables. In addition, Clustering Lasso encourages selection of clusters of variables, so that variables having the same mechanism of predicting the response variable will be selected together in the regression model. A real microarray data example and simulation studies show that Clustering Lasso outperforms Lasso in terms of prediction performance, particularly when there is collinearity among variables and/or when the number of predictors is larger than the number of observations. The Clustering Lasso paths can be obtained using any established algorithm for Lasso solution. An algorithm is proposed to construct variable correlation structures and to compute Clustering Lasso paths efficiently.

Background Adherence to self-management recommendations is critical for patients with chronic disease. Compared to nonsmokers, smokers with conditions such as diabetes, HIV, and heart disease are less likely to adhere to provider recommendations. Regarding lung disease, asthma and COPD can be caused and/or exacerbated by smoking, however little is known on the relationship between adherence and smoking status in these patients. The purpose of this study was to characterize the relationship between smoking status and adherence to multiple measures of self-care- including medication taking, medication filling, appointment keeping, yearly vaccinations, carrying medical supplies, and healthcare utilization- in patients with asthma and/or COPD. In addition to smoking status, we also included an examination of these measures by race/ethnicity, gender, and diagnosis. Methods This study employed a cross-sectional design on a convenience sample of n = 84 patients (40–64 years old) with a diagnosis of asthma and/or COPD. The study was conducted between November 2015 and February 2016 in the waiting rooms of the outpatient pulmonary clinics at the University Medical Center of New Orleans. Patients completed surveys while awaiting their clinic appointments. Smoking status, gender, race, and diagnosis were explored as predictors of adherence using descriptive statistics, chi square, and regression analyses. Results Compared to nonsmokers, smokers were less adherent to medication filling (p

The objective of the present study was to determine which of six bonding protocols yielded a clinically acceptable shear bond strength (SBS) of metal orthodontic brackets to CAD/CAM lithium disilicate porcelain restorations. A secondary aim was to determine which bonding protocol produced the least surface damage at debond.Sixty lithium disilicate samples were fabricated to replicate the facial surface of a mandibular first molar using a CEREC CAD/CAM machine. The samples were split into six test groups, each of which received different mechanical/chemical pretreatment protocols to roughen the porcelain surface prior to bonding a molar orthodontic attachment. Shear bond strength testing was conducted using an Instron machine. The mean, maximum, minimal, and standard deviation SBS values for each sample group including an enamel control were calculated. A t-test was used to evaluate the statistical significance between the groups.No significant differences were found in SBS values, with the exception of surface roughening with a green stone prior to HFA and silane treatment. This protocol yielded slightly higher bond strength which was statistically significant.Chemical treatment alone with HFA/silane yielded SBS values within an acceptable clinical range to withstand forces applied by orthodontic treatment and potentially eliminates the need to mechanically roughen the ceramic surface.

Introduction This study aimed to determine the feasibility of using electronic health record (EHR) data from a federally qualified health center (FQHC) to assess the association between street connectivity, a measure of walkability for the local environment, and BMI obtained from EHRs. Methods The study included patients who visited Daughters of Charity clinics in 2012–2013. A total of 31,297 patients were eligible, of which 28,307 were geocoded. BMI and sociodemographic information were compiled into a de-identified database. The street connectivity measure was intersection density, calculated as the number of three-way or greater intersections per unit area. Multilevel analyses of BMI, measured on 17,946 patients who were aged ≥20 years, not pregnant, had complete sociodemographic information, and a BMI value that was not considered an outlier, were conducted using random intercept models. Results Overall, on average, patients were aged 44.1 years, had a BMI of 30.2, and were mainly non-Hispanic black (59.4%). An inverse association between BMI and intersection density was observed in multilevel models controlling for age, gender, race, and marital status. Tests for multiple interactions were conducted and a significant interaction between race and intersection density indicated the decrease in BMI was strongest for non-Hispanic whites (decreased by 2) compared with blacks or Hispanics (decreased by 0.6) ( p =0.0121). Conclusions EHRs were successfully used to assess the relationship between street connectivity and BMI in a multilevel framework. Increasing street connectivity levels measured as intersection density were inversely associated with directly measured BMI obtained from EHRs, demonstrating the feasibility of the approach.

Identification of the type of disease pattern and spread in a field is critical in epidemiological investigations of plant diseases. For example, an aggregation pattern of infected plants suggests that, at the time of observation, the pathogen is spreading from a proximal source. Conversely, a random pattern suggests a lack of spread from a proximal source. Most of the existing methods of spatial pattern analysis work with only one variety of plant at each location and with uniform genetic disease susceptibility across the field. Pecan orchards, used in this study, and other orchard crops are usually composed of different varieties with different levels of susceptibility to disease. A new measure is suggested to characterize the spatio-temporal transmission patterns of disease; a Monte Carlo test procedure is proposed to test whether the transmission of disease is random or aggregated. In addition, we propose a mixed-transmission model, which allows us to quantify the degree of aggregation effect.

Purpose: Over the past three decades, hepatocellular carcinoma (HCC) is one of the few cancers for which incidence has increased in the United States (U.S.). While chronic infection with hepatitis C virus is a leading risk factor for HCC, other known risks that are more prevalent in the U.S. population, including alcohol abuse, metabolic disease, and obesity, have also contributed to increasing rates. There is growing recognition that social and/or nutritive stress represent exposures that negatively affect individual health. These factors are believed to be socially determined by conditions in an individual's neighborhood environment. We designed a population-based study to identify potential social determinants of the increase in HCC by investigating the association of HCC incidence with neighborhood environments characterized by concentrated disadvantage. Methods: Data from the Louisiana Tumor Registry, a participant of the National Cancer Institute's Surveillance and Epidemiology End Results (SEER) program, were used in the analysis of primary HCC diagnosed from 2008 to 2012. Cases were geocoded to census tract of residence by address at the time of diagnosis. Average annual incidence rates were calculated for age, race, and sex groups within census tracts based on 2010 US Census data. Neighborhood concentrated disadvantage index (CDI) for each census tract was calculated in accordance with the PhenX Toolkit protocol. We excluded census tracts outside of metropolitan statistical areas, as well as any tract with less than 500 people or zero households, from the analyses. Multilevel log-binomial models were used to evaluate neighborhood variation and quantify the degree of association of CDI with HCC incidence. Results: The study included 1,407 cases of HCC diagnosed from 2008 to 2012. Univariate analyses indicated significantly greater incidence of HCC among males (p Discussion/Conclusion: We have found neighborhood concentrated disadvantage to be a significant risk factor for the development of HCC. We also determined that differential exposure to neighborhoods of concentrated disadvantage contributed to observed racial disparities in HCC in Louisiana. Our results suggest that increasing rates of HCC, and existing racial disparities in the disease, are partially driven by social contexts of adverse living environments. Citation Format: Denise M. Danos, Tekeda F. Ferguson, Neal Simonsen, Claudia Leonardi, Qingzhao Yu, Xiao-Cheng Wu, Richard Scribner. Social determinants of hepatocellular carcinoma in Louisiana [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr A41.

Purpose Colorectal cancer (CRC) continues to demonstrate racial disparities in incidence and survival in the United States. This study investigates the role of neighborhood concentrated disadvantage in racial disparities in CRC incidence in Louisiana. Methods Louisiana Tumor Registry and U.S. Census data were used to assess the incidence of CRC diagnosed in individuals 35 years and older between 2008 and 2012. Neighborhood concentrated disadvantage index (CDI) was calculated based on the PhenX Toolkit protocol. The incidence of CRC was modeled using multilevel binomial regression with individuals nested within neighborhoods. Results Our study included 10,198 cases of CRC. Adjusting for age and sex, CRC risk was 28% higher for blacks than whites (risk ratio [RR] = 1.28; 95% confidence interval [CI] = 1.22–1.33). One SD increase in CDI was associated with 14% increase in risk for whites (RR = 1.14; 95% CI = 1.10–1.18) and 5% increase for blacks (RR = 1.05; 95% CI = 1.02–1.09). After controlling for differential effects of CDI by race, racial disparities were not observed in disadvantaged areas. Conclusion CRC incidence increased with neighborhood disadvantage and racial disparities diminished with mounting disadvantage. Our results suggest additional dimensions to racial disparities in CRC outside of neighborhood disadvantage that warrants further research.

Given the growing availability of multilevel data from national surveys, researchers interested in contextual effects may find themselves with a small number of individuals per group. Although there is a growing body of literature on sample size in multilevel modelling, few have explored the impact of group sizes of less than five.In a simulated analysis of real data, the impact of a group size of less than five was examined on both a continuous and dichotomous outcome in a simple two-level multilevel model. Models with group sizes one to five were compared with models with complete data. Four different linear and logistic models were examined: empty models; models with a group-level covariate; models with an individual-level covariate and models with an aggregated group-level covariate. The study evaluated further whether the impact of small group size differed depending on the total number of groups.When the number of groups was large (N=459), neither fixed nor random components were affected by small group size, even when 90% of tracts had only one individual per tract and even when an aggregated group-level covariate was examined. As the number of groups decreased, the SE estimates of both fixed and random effects were inflated. Furthermore, group-level variance estimates were more affected than were fixed components.Datasets in which there is a small to moderate number of groups, with the majority of very small group size (n5), size may fail to find or even consider a group-level effect when one may exist and also may be underpowered to detect fixed effects.

It is known that when there are heavy-tailed errors or outliers in the response, the least squares methods may fail to produce a reliable estimator. In this paper, we proposed a generalized Huber criterion which is highly flexible and robust for large errors. We applied the new criterion to the bridge regression family, called robust and sparse bridge regression (RSBR). However, to get the RSBR solution requires solving a nonconvex minimization problem, which is a computational challenge. On the basis of recent advances in difference convex programming, coordinate descent algorithm and local linear approximation, we provide an efficient computational algorithm that attempts to solve this nonconvex problem. Numerical examples show the proposed RSBR algorithm performs well and suitable for large-scale problems.

Aim The present study examined the effect of topical fluoride treatment on the shear bond strength (SBS) of orthodontic brackets using single-dose fluoride varnishes and assessed according to different post-application times and the pattern of debond. Methods Of the 105 extracted human mandibular premolars used in the study, 70 were subjected to the SBS test and the remaining 35 to the Adhesive Remnant Index (ARI) test. The teeth were divided into a control group and six test groups: Kolorz®ClearShieldTM 5%NaFl varnish Day 1, 8, and 15; and VanishTM 5%NaFl varnish Day 1, 8, and 15. The samples were coated with their respective varnish, following which, brackets were bonded. Each specimen was subjected to a shear force in a universal testing machine until failure. Data were analysed using the analysis of variance (ANOVA). Results At all time intervals, the mean SBS of the Vanish groups was not significantly different from the control group, and the shear strength in the ClearShield groups was significantly higher than the control and Vanish groups, except at Day 8 (no difference). For the same bonding material, there was no significant difference in mean SBS over different time intervals. ARI scores showed no significant difference between the groups. Conclusion The application of single-dose fluoride varnish, irrespective of the length of time between the fluoride treatment and bonding procedure, does not negatively affect the shear bond strength of orthodontic brackets.