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1.
Med Dosim ; 45(3): 284-292, 2020.
Article in English | MEDLINE | ID: mdl-32223971

ABSTRACT

BACKGROUND: Aperture shape controller (ASC) is a recently introduced leaf sequencer that controls the complexity of multileaf collimator apertures in the Photon Optimizer algorithm of the Eclipse treatment planning system. The aim of this study is to determine if the ASC can reduce plan complexity and improve verification results, without compromising plan quality. METHODS: Thirteen plans grouped into cohorts of head and neck/brain, breast/chest and pelvis were reoptimised using the same optimization as the non-ASC setting for low, moderate and high ASC settings. These plans were analyzed using plan quality indices such as the conformity index and homogeneity index in addition to dose-volume histogram based analysis on PTVs and organ at risks. Complexity assessments were performed using metrics such as average leaf pair opening, modulation complexity scores, relative monitor units (MU) and treatment time. Monitor unit per gantry angle variations were also analyzed. A third-party algorithm was also used to assess 3D dose distributions produced using the new leaf sequencer tool. Deliverability for the final multileaf collimator distribution was quantified using portal dose image prediction based gamma analysis. RESULTS: Plan conformality assessments showed comparable results and no significant plan degradation for plans reoptimised using ASC. Reduction in overall MU distributions were seen in some cases using higher ASC however, no overall trends were observed. In general, treatment deliverability, assessed using gamma analysis did not improve drastically however MU per degree distribution in 1 case improved when reoptimised using ASC. Treatment MUs generally reduced when ASC settings were used whilst in 1 case an increase in the treatment time factor > 1.8 was observed. The third-party algorithm assessment showed an underestimation of dose calculations for all cohorts used in this study when a higher ASC setting is used. CONCLUSIONS: The impact of using ASC in treatment plans was characterised in this study. Although plan complexity marginally improved when using higher ASC settings, no consensus could be reached based on metrics analyzed in this study. A reduction in MU distribution was observed with increasing ASC settings in most cases. This study recommends that ASC to be used as an additional tool only to test its suitability to reduce plan complexity.


Subject(s)
Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated , Algorithms , Cohort Studies , Female , Humans , Male , Radiotherapy Dosage
2.
J Appl Clin Med Phys ; 19(5): 739-748, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29956454

ABSTRACT

PURPOSE: The aim of this work was to present the development and example application of an automated data mining software platform that preforms bulk analysis of results and patient data passing through the 3D plan and delivery QA system, Mobius3D. METHODS: Python, matlab, and Java were used to create an interface that reads JavaScript Object Notation (JSON) created for every approved Mobius3D pre-treatment plan-check. The aforementioned JSON files contain all the information for every pre-treatment QA check performed by Mobius3D, including all 3D dose, CT, structure set information, as well as all plan information and patient demographics. Two Graphical User Interfaces (GUIs) were created, the first is called Mobius3D-Database (M3D-DB) and presents the check results in both filterable tabular and graphical form. These data are presented for all patients and includes mean dose differences, 90% coverage, 3D gamma pass rate percentages, treatment sites, machine, beam energy, Multi-Leaf Collimator (MLC) mode, treatment planning system (TPS), plan names, approvers, dates and times. Group statistics and statistical process control levels are then calculated based on filter settings. The second GUI, called Mobius3D organ at risk (M3DOAR), analyzes dose-volume histogram data for all patients and all Organs-at-Risk (OAR). The design of the software is such that all treatment parameters and treatment site information are able to be filtered and sorted with the results, plots, and statistics updated. RESULTS: The M3D-DB software can summarize and filter large numbers of plan-checks from Mobius3D. The M3DOAR software is also able to analyze large amounts of dose-volume data for patient groups which may prove useful in clinical trials, where OAR doses for large numbers of patients can be compared and correlated. Target DVHs can also be analyzed en mass. CONCLUSIONS: This work demonstrates a method to extract the large amount of treatment data for every patient that is stored by Mobius3D but not easily accessible. With scripting, it is possible to mine this data for research and clinical trials as well as patient and TPS QA.


Subject(s)
Data Mining , Algorithms , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Radiotherapy, Intensity-Modulated , Software
3.
Health Promot Pract ; 19(3): 377-389, 2018 05.
Article in English | MEDLINE | ID: mdl-29161902

ABSTRACT

This article describes the process and results associated with the organizational-level recruitment of Black barbershops into Fitness in the Shop (FITShop), a 6-month barbershop-based intervention study designed to promote physical activity among Black men. Organizational-level recruitment activities included (1) a telephone call to prospective barbershop owners to assess their interest and eligibility for participation, (2) an organizational eligibility letter sent to all interested and eligible barbershops, (3) a visit to interested and eligible barbershops, where a culturally sensitive informational video was shown to barbershop owners to describe the study activities and share testimonies from trusted community stakeholders, and (4) a signed agreement with barbershop owners and barbers, which formalized the organizational partnership. Structured interviews were conducted with owners of a total of 14 enrolled barbershops, representing 30% of those determined to be eligible and interested. Most enrolled shops were located in urban settings and strip malls. Barbershop owners were motivated to enroll in the study based on commitment to their community, perceived client benefits, personal interest in physical activity, and a perception that the study had potential to make a positive impact on the barbershop and on reducing health disparities. Results offer important insights about recruiting barbershops into intervention trials.


Subject(s)
Barbering , Black or African American , Health Promotion/organization & administration , Health Status Disparities , Adult , Aged , Exercise , Humans , Interviews as Topic , Male , Middle Aged , Motivation , North Carolina , Prospective Studies , Qualitative Research , Young Adult
5.
Front Public Health ; 5: 47, 2017.
Article in English | MEDLINE | ID: mdl-28349049

ABSTRACT

The southeast is identified as the epicenter of the nation's human immunodeficiency virus (HIV) epidemic, accounting for nearly 44% of all persons living with a HIV diagnosis in the United States. HIV stigma and knowledge have been cited as some of the complex factors increasing risk of acquiring HIV within African-American communities. We sought to understand how HIV knowledge and HIV-related stigma impact HIV testing experience among young Black adults who completed a community-based participatory research survey in a Southeastern city. Survey measures were developed with active engagement among the research team and community members, with the goal of balancing community knowledge, interests and concerns with scientific considerations, and the realities of funding and the project timeline. A total of 508 of the 513 audio computer-assisted self-interview questionnaires completed were analyzed. Eighty-one percent of participants had ever tested and had an intention-to-test for HIV in the next 12 months. Overall, analyses revealed low HIV-related stigma and relatively moderate to high HIV knowledge among young Black adults in the Southeastern city. Logistic regression indicated that having ever tested for HIV was positively correlated with HIV knowledge [odds ratio (OR): 1.50; 95% confidence interval (CI): 1.23-1.84, p < 0.001], but inversely correlated with low HIV-related stigma (OR: 0.08; 95% CI: 0.01-0.76, p < 0.03). However, there were no significant relationships between HIV-related stigma, HIV knowledge, and intention-to test for HIV in the future. These findings suggest that reducing HIV-related stigma and increasing HIV knowledge are not sufficient in promoting HIV testing (i.e., intention-to-test) among young Black adults in this city, unless specific emphasis is placed on addressing internalized HIV-related stigma and misperceptions about HIV prevention and control.

6.
J Appl Clin Med Phys ; 18(1): 59-65, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28291923

ABSTRACT

In radiation therapy, calculation of dose within the patient contains inherent uncertainties, inaccuracies, limitations, and the potential for random error. Thus, point dose-independent verification of such calculations is a well-established process, with published data to support the setting of both action levels and tolerances. Mobius3D takes this process one step further with a full independent calculation of patient dose and comparisons of clinical parameters such as mean target dose and voxel-by-voxel gamma analysis. There is currently no published data to directly inform tolerance levels for such parameters, and therefore this work presents a database of 1000 Mobius3D results to fill this gap. The data are tested for normality using a normal probability plot and found to fit this distribution for three sub groups of data; Eclipse, iPlan and the treatment site Lung. The mean (µ) and standard deviation (σ) of these sub groups is used to set action levels and tolerances at µ ± 2σ and µ ± 3σ, respectively. A global (3%, 3 mm) gamma tolerance is set at 88.5%. The mean target dose tolerance for Eclipse data is the narrowest at ± 3%, whilst iPlan and Lung have a range of -5.0 to 2.2% and -1.8 to 5.0%, respectively. With these limits in place, future results failing the action level or tolerance will fall within the worst 5% and 1% of historical results and an informed decision can be made regarding remedial action prior to treatment.


Subject(s)
Algorithms , Databases, Factual , Lung Neoplasms/radiotherapy , Monte Carlo Method , Quality Control , Radiotherapy Planning, Computer-Assisted/standards , Radiotherapy, Intensity-Modulated/standards , Clinical Protocols , Humans , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods
7.
AIDS Educ Prev ; 28(1): 59-76, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26829257

ABSTRACT

Black Americans continue to have higher rates of HIV disease than other races/ethnicities. Conventional individual-level risk behaviors do not fully account for these racial/ethnic disparities. Sexual concurrency may help explain them. Respondent-driven sampling (RDS) was used to enroll 508 sexually active 18- to 30-year-old Black men and women in Durham, North Carolina in a cross-sectional survey on HIV-related topics. Consistent condom use was low for all participants, especially with steady partners. Concurrent partnerships in the past 6 months were relatively common for both men (38%) and women (25%). In general, men involved in concurrent relationships engaged in more risk behaviors than other men (e.g., inconsistent condom use and alcohol and drug use). A majority of concurrent partnerships involved steady partners. HIV-prevention programs should address the risks of concurrency and factors that discourage condom use, especially with steady partners with whom condom use is particularly low.


Subject(s)
Black or African American/psychology , Condoms/statistics & numerical data , HIV Infections/prevention & control , Sexual Behavior/psychology , Sexual Partners/psychology , Adolescent , Adult , Black or African American/statistics & numerical data , Cross-Sectional Studies , Female , HIV Infections/epidemiology , HIV Infections/psychology , Humans , Male , North Carolina/epidemiology , Risk-Taking , Sexual Behavior/ethnology , Sexual Behavior/statistics & numerical data , Substance-Related Disorders , Surveys and Questionnaires , Young Adult
8.
Am J Community Psychol ; 55(3-4): 433-43, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25893817

ABSTRACT

African Americans are disproportionately affected by the HIV epidemic inclusive of men who have sex with men, heterosexual men, and women. As part of a community-based participatory research study we assessed HIV testing experience among sexually active 18-30 year old Black men and women in Durham, NC. Of 508 participants, 173 (74 %) men and 236 (86 %; p = 0.0008) women reported ever being tested. Barriers to testing (e.g., perceived risk and stigma) were the same for men and women, but men fell behind mainly because a primary facilitator of testing-routine screening in clinical settings-was more effective at reaching women. Structural and behavioral risk factors associated with HIV infection were prevalent but did not predict HIV testing experience. Reduced access to health care services for low income Black young adults may exacerbate HIV testing barriers that already exist for men and undermine previous success rates in reaching women.


Subject(s)
AIDS Serodiagnosis/statistics & numerical data , Black or African American/psychology , Unsafe Sex/statistics & numerical data , Adolescent , Adult , Black or African American/statistics & numerical data , Community-Based Participatory Research , Cross-Sectional Studies , Female , Humans , Male , North Carolina/epidemiology , Risk Factors , Sexual Behavior/psychology , Sexual Behavior/statistics & numerical data , Stereotyping , Substance-Related Disorders/epidemiology , Substance-Related Disorders/psychology , Unsafe Sex/psychology , Young Adult
9.
Am J Mens Health ; 9(4): 262-73, 2015 Jul.
Article in English | MEDLINE | ID: mdl-24972715

ABSTRACT

African American (AA) men have a higher prevalence of many chronic disease risk behaviors compared to Caucasian men, including physical inactivity. Innovative ways to reach AA men with interventions to increase physical activity (PA) and decrease other key risk factors are needed to reduce health disparities in this population. The barbershop is a natural but underutilized setting for reaching AA men. In the Fitness in the Shop (FITShop) study, shop owners, barbers, and customers were recruited from four local barbershops to complete structured interviews and customer focus groups. We assessed knowledge, perceived barriers, and interests/concerns about PA, as well as explored how to best intervene in the barbershop. Barbers and customers endorsed the idea of receiving health and PA information in the barbershop. These formative research results generated information and strategies for developing a multilevel barbershop-based health intervention to promote PA in the barbershop. This article describes the formative research results and how PRECEDE was used to develop a culturally and contextually appropriate, multilevel barbershop-based intervention designed to promote PA and to reduce chronic disease disparities among AA men.


Subject(s)
Black or African American , Chronic Disease/prevention & control , Community-Based Participatory Research/organization & administration , Health Knowledge, Attitudes, Practice/ethnology , Health Promotion/organization & administration , Motor Activity/physiology , Social Behavior , Adolescent , Adult , Aged , Barbering , Chronic Disease/ethnology , Community-Based Participatory Research/methods , Cultural Competency , Focus Groups , Health Promotion/methods , Humans , Interviews as Topic , Male , Middle Aged , Models, Organizational , North Carolina/epidemiology , Protective Factors , Risk Factors , Young Adult
10.
J Appl Clin Med Phys ; 12(1): 3320, 2010 Sep 28.
Article in English | MEDLINE | ID: mdl-21330979

ABSTRACT

Since the clinical implementation of novel rotational forms of intensity-modulated radiotherapy, a variety of planning studies have been published that reinforce the major selling points of the technique. Namely, comparable or even improved dose distributions with a reduction in both monitor units and treatment times, when compared with static gantry intensity-modulated radiotherapy. Although the data are promising, a rigorous approach to produce these plans has yet to be established. As a result, this study outlines a robust and streamlined planning strategy with a concentration on RapidArc class solutions for prostate with a simultaneous integrated boost. This planning strategy outlines the field setup, recommended starting objectives, required user interactions to be made throughout optimization and post-optimization adjustments. A comparative planning study, with static gantry IMRT, is then presented as justification for the planning strategy itself. A variety of parameters are evaluated relating to both the planning itself (optimization and calculation time) and the plans that result. Results of this comparative study are in line with previously published data, and the planning process is streamlined to a point where the RapidArc optimization time takes 15 ± 1.3 minutes. Application of this planning strategy reduces the dependence of the produced plan on the experience of the planner, and has the potential to streamline the planning process within radiotherapy departments.


Subject(s)
Prostatic Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted/methods , Femur Head/radiation effects , Humans , Male , Radiation Tolerance , Radiotherapy Dosage , Rectum/radiation effects , Time Factors , Urinary Bladder/radiation effects
11.
Health Promot Pract ; 10(4): 527-36, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19098262

ABSTRACT

Policy advocacy is increasingly recognized as a crucial component of the training provided to health educators but relatively few universities offer advocacy training as part of their professional preparation programs for health educators. Historically Black colleges and universities (HBCUs) represent a natural setting for creating strong Black leaders in tobacco policy advocacy. This case study focuses on experiential education at an HBCU to develop advocacy skills around tobacco issues among Black college students. The authors describe the structure and content of two tobacco policy courses, their efforts to evaluate these courses, and the lessons they learned planning and conducting them. They believe their experience can prove useful to others developing curricula for teaching policy advocacy skills to health education students.


Subject(s)
Black or African American/education , Health Educators/education , Health Policy , Smoking Prevention , Universities/organization & administration , Humans , Leadership , Organizational Case Studies , Program Evaluation , Social Change
12.
Prev Chronic Dis ; 5(3): A82, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18558032

ABSTRACT

INTRODUCTION: Considerable evidence exists that little cigars are popular among African American adolescents and young adults who smoke. However, few studies have been published on the use of this tobacco product by young blacks in the United States. This research investigated little-cigar use among students at a historically black university in the southeastern United States. METHODS: As a follow-up to a survey on tobacco use among freshmen that revealed unexpectedly high rates of little-cigar use, 3 focus groups were conducted with current or former smokers of little cigars. Topics included preferred brands of little cigars, preference for little cigars over cigarettes, social contexts for smoking little cigars, perceived health risks of smoking little cigars relative to smoking cigarettes, and thoughts about quitting. RESULTS: Focus group participants preferred little cigars to cigarettes for various reasons, among them taste, smell, a better "buzz," social purposes, status, and perceptions that smoking little cigars is less addictive and less harmful than smoking cigarettes. Opinions on health risks varied; some participants believed that health risks can be reduced by removing the inner liner of little cigars. CONCLUSION: Use of little cigars should be addressed in tobacco research, use prevention, and use cessation efforts, targeting students at historically black colleges and perhaps other young African Americans. Results also suggest that clear distinctions should be made among cigarettes, little cigars, and cigars, and that tobacco use prevention and cessation programs should debunk myths that little cigars are a safe alternative to cigarettes. Study findings should be confirmed and elucidated through additional research.


Subject(s)
Black or African American , Health Knowledge, Attitudes, Practice , Smoking/ethnology , Adolescent , Adult , Female , Focus Groups , Humans , Male , Marijuana Smoking/ethnology , Southeastern United States/epidemiology , Students , Universities
13.
Cancer Epidemiol Biomarkers Prev ; 14(12): 2978-81, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16365020

ABSTRACT

Receptivity to genetic testing for lung cancer susceptibility was assessed among African American college freshmen, who held attitudes favorable towards or had experimented with cigarette smoking. Students (n = 95) completed a telephone survey that assessed beliefs about genetics and lung cancer risk, interest in genetic testing, and expectations about the test outcome. Interest in being tested was moderately high (mean, 5; SD, 2.2; scale of 1-7) and highest among those who believed lung cancer was influenced by genetics (r = 0.22, P < 0.05) and those who expected to be at high risk (r = 0.27, P < 0.05). Overall, 34% thought if tested, the result would show high risk for lung cancer. In multivariate analyses, students' test result expectation was the only significant predictor of interest in testing. Those who believed the test would show them to be at higher risk were thrice more likely to be interested in testing than those who thought the test would show that they were at lower risk (odds ratio, 2.99; confidence interval, 1.03-8.64; P = 0.04). Future research is needed to understand how young adults will respond to genetic susceptibility feedback that confirms or contradicts their expectations about personal risks of smoking.


Subject(s)
Black or African American/psychology , Genetic Predisposition to Disease , Genetic Testing/psychology , Lung Neoplasms/genetics , Smoking/epidemiology , Students/psychology , Adult , Humans , Intention , Lung Neoplasms/epidemiology , North Carolina/epidemiology , Pilot Projects , Risk Assessment
14.
Health Educ Behav ; 30(5): 550-63, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14582597

ABSTRACT

Funding agencies are using technical assistance (TA) to strengthen the evaluation capacity of community-based organizations (CBOs) engaged in HIV prevention efforts. The authors used qualitative methods to identify the types of evaluation TA needed by CBOs, to understand CBOs' past experiences with evaluation TA, and to elicit ideas for optimal delivery of evaluation TA. Assistance in developing evaluation tools and data analysis were the most commonly cited needs. Preferred TA providers were characterized as having practical expertise, accessibility, cultural competence, communication skills, and collaboration skills. Critical elements of an ideal TA system were adequate funding, program-specific TA, and extensive interaction between TA providers and CBO staff. Study data were used to generate a set of recommendations for health educators and others who may provide CBOs with TA for evaluating prevention programs.


Subject(s)
Community Health Services/organization & administration , HIV Infections/prevention & control , Program Evaluation/methods , Community Health Services/standards , Health Planning Technical Assistance , Humans , Professional Competence , Qualitative Research , United States
15.
Exp Mol Pathol ; 74(3): 244-55, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12782011

ABSTRACT

Nonhealing wounds of the lower equine limb represent a challenging model. The platelet is a natural source of a myriad of growth factors and cytokines that promote wound healing. This study evaluates the potential of platelet derived factors to enhance wound healing in the lower equine limb. Platelets were isolated from horse blood and activated with thrombin, a process known to induce growth factor release. This produced a platelet gel composed of platelet-rich plasma (PRP). To test this all-natural wound healant, 2.5-cm(2) full thickness cutaneous wounds were created below the knee and hock of a thoroughbred horse. Wounds were treated with PRP gel or left untreated. Sequential wound biopsies collected at Days 7, 36, and 79 postwounding permitted comparison of the temporal expression of differentiation markers and wound repair. To test the hypothesis that wounds treated with PRP gel exhibit more rapid epithelial differentiation and enhanced organization of dermal collagen compared to controls, tissues were stained for cytokeratin 10, a suprabasal differentiation marker, and the reestablishment of collagen was evaluated by trichrome staining. PRP gel-treated wounds at Day 7 expressed intense cytokeratin 10 staining near the wound junction in suprabasal epidermal layers, while staining in control tissues was less intense and restricted to apical epidermal layers distal to the wound junction. By Day 79, the staining was equal in both groups. However, PRP gel-treated wounds at Day 79 contained abundant, dense collagen bundles oriented parallel to each other and to the overlying epithelium, whereas control tissues contained fewer collagen fibers that were oriented randomly. Thus, treatment of wounds with PRP gel induced accelerated epithelial differentiation and produced tissue with organized, interlocking collagen bundles. This study reveals that this novel all-natural wound healant induced wound repair in injuries previously deemed untreatable.


Subject(s)
Blood Platelets/metabolism , Horse Diseases/physiopathology , Platelet-Derived Growth Factor/metabolism , Skin/injuries , Wound Healing/physiology , Animals , Blood Platelets/drug effects , Cell Differentiation , Collagen/metabolism , Enzyme-Linked Immunosorbent Assay , Gels/chemistry , Horse Diseases/drug therapy , Horse Diseases/pathology , Horses , Immunoenzyme Techniques , Keratin-10 , Keratins/analysis , Keratins/metabolism , Male , Platelet-Derived Growth Factor/administration & dosage , Platelet-Derived Growth Factor/analysis , Regeneration , Skin/pathology , Thrombin/pharmacology , Transforming Growth Factor beta/analysis , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta1 , Wound Healing/drug effects
16.
AIDS Educ Prev ; 14(3 Suppl A): 38-48, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12092935

ABSTRACT

Funding agencies are using technical assistance to promote evaluation of their community-based HIV prevention programs. Using qualitative methods, we identified 11 factors that hinder and facilitate evaluation within community-based organizations (CBOs): staff perceptions, availability of funding, data collection, data validity, data utility, technical assistance, effects on services, effects on funding, staff skills, tools and technology, and expectations of the funding agency. Using these factors, we developed eight strategies to promote CBO evaluation. These strategies go beyond the traditional role of technical assistance and address the broader context within which CBOs evaluate their programs. Funding agencies and technical assistance providers can use these strategies to enhance CBO evaluation, which may result in more and better quality evaluations and, ultimately, improvements in the effectiveness of HIV prevention services.


Subject(s)
Community Health Services/organization & administration , HIV Infections/prevention & control , Preventive Health Services/organization & administration , Program Evaluation/methods , Attitude of Health Personnel , Community Participation , Data Collection , Efficiency, Organizational , Humans , Preventive Health Services/economics , Preventive Health Services/standards , Qualitative Research
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