Mutual Information for Testing Gene-Environment Interaction

Despite current enthusiasm for investigation of gene-gene interactions and gene-environment interactions, the essential issue of how to define and detect gene-environment interactions remains unresolved. In this report, we define gene-environment interactions as a stochastic dependence in the context of the effects of the genetic and environmental risk factors on the cause of phenotypic variation among individuals. We use mutual information that is widely used in communication and complex system analysis to measure gene-environment interactions. We investigate how gene-environment interactions generate the large difference in the information measure of gene-environment interactions between the general population and a diseased population, which motives us to develop mutual information-based statistics for testing gene-environment interactions. We validated the null distribution and calculated the type 1 error rates for the mutual information-based statistics to test gene-environment interactions using extensive simulation studies. We found that the new test statistics were more powerful than the traditional logistic regression under several disease models. Finally, in order to further evaluate the performance of our new method, we applied the mutual information-based statistics to three real examples. Our results showed that P-values for the mutual information-based statistics were much smaller than that obtained by other approaches including logistic regression models.

Human Trafficking: Awareness, Data and Policy

The implications of the new research presented in Volume 2, Issue 1 (Human Trafficking) of the Journal of Applied Research on Children are explored, calling attention to the need for increased awareness, greater availability of data, and proactive policy solutions to combat child trafficking.

Symmetric inverse consistent nonlinear registration driven by mutual information.

A nonlinear viscoelastic image registration algorithm based on the demons paradigm and incorporating inverse consistent constraint (ICC) is implemented. An inverse consistent and symmetric cost function using mutual information (MI) as a similarity measure is employed. The cost function also includes regularization of transformation and inverse consistent error (ICE). The uncertainties in balancing various terms in the cost function are avoided by alternatively minimizing the similarity measure, the regularization of the transformation, and the ICE terms. The diffeomorphism of registration for preventing folding and/or tearing in the deformation is achieved by the composition scheme. The quality of image registration is first demonstrated by constructing brain atlas from 20 adult brains (age range 30-60). It is shown that with this registration technique: (1) the Jacobian determinant is positive for all voxels and (2) the average ICE is around 0.004 voxels with a maximum value below 0.1 voxels. Further, the deformation-based segmentation on Internet Brain Segmentation Repository, a publicly available dataset, has yielded high Dice similarity index (DSI) of 94.7% for the cerebellum and 74.7% for the hippocampus, attesting to the quality of our registration method.

Practice and attitude differences in physician cigarette use: A study of prevalence, physicians' role, and smoking policy awareness in Dubai, UAE

The use of tobacco products ruins the health of millions of people around the world. On average, tobacco users die nearly seven years earlier than non-tobacco users. n1 Cigarette smoking is a particular concern in the developing countries of the Middle East and Gulf Cooperation Council (GCC) region where smoking prevalence is expected to increase. This is due to the tobacco industry's vigorous commercial and marketing activities. n3 Smoking prevalence among physicians is considered to be an effective indicator of a society's readiness to identify the smoking epidemic and its related health diseases. n4 There is a lack of detailed data on the smoking prevalence among healthcare professionals, particularly physicians, in the United Arab Emirates (UAE). This cross sectional study is the first to address smoking practices among physicians working at the Department of Health and Medical Services (DOHMS); in Dubai, UAE. ^ This study describes the cigarette smoking prevalence among DOHMS Physicians, physician attitudes towards tobacco use and tobacco bans; physician attitudes towards smoking cessation techniques (among smokers and non-smokers); and physician awareness of official anti-smoking policies. Data for the study was collected through the use of an adapted WHO standardized questionnaire, the Global Health Professionals Survey. The questionnaire was administered by the researcher to physicians (n=288) at their work place. Date was analyzed using the SPSS analytic software program. ^ Twelve percent of DOHMS physicians smoked cigarettes. Regardless of smoking status, the majority supported a tobacco ban in hospitals and public places, and a ban on tobacco advertising. There is a significant relationship between physician smoking status and discussing risks of tobacco use (p < 0.05). Non-smoking physicians reported spending more time with patients discussing hazards of smoking (p < 0.01). Non-smokers reported providing more counseling than their smoking colleagues. The majority of DOHMS physicians (63%) reported a lack of knowledge about 5As/ 5Rs. The majority of physicians also reported they are aware of hospital smoking policies that restrict smoking. Regardless of physician smoking status, DOHMS physicians are not very actively involved in smoking cessation activities. This cross sectional study is the first to address smoking programs, policies, and practices among physicians in Dubai, UAE. Findings support the need for increased physical smoking cessation training as well as the development of smoking cessation programs for tobacco control, and programs with a focus on physician participation in reducing tobacco and cigarette use among the general population.^

Mexican Americans' awareness, knowledge, and beliefs of hypertension

Cardiovascular disease (CVD) is the number one cause of death for people in Texas as well as Mexico. The progressive morbidity and mortality of CVD can be prevented initially and controlled through regular health screenings or visits to the physician where health markers such as hypertension can be detected and treated. Yet, many people go unaware of existing hypertension not only due to lack of access to health care but to their own personal beliefs, ideas, or perceived barriers that prevent them from seeking preventative health care. ^ The main purpose of this study was to evaluate whether individuals of Mexican origin, who have some form of medical coverage, posses more knowledge, more perceived severity, less perceived barriers, and greater self-efficacy in regards to hypertension than those individuals who have no medical coverage. This was done by addressing the following specific aims: 1.To evaluate the association between individuals who have health care coverage and those who do not have health care coverage in regards to their beliefs of hypertension; 2. To evaluate if there exists a variation among the respondents demographic data and their beliefs of hypertension. ^ The total number of respondents were 150; with 75 being from Cuidad Juarez, and 75 being from El Paso, Texas. The results indicated that the individuals with some form of medical coverage perceived themselves to be more susceptible to suffering a cardiac event or developing heart disease than those who had no form of medical coverage. The individuals with some form of health care coverage also found themselves having less perceived barriers than those who had no health care coverage. The level of education seemed to have some association with individuals perceiving themselves as being susceptible to experiencing a cardiac event if they do not control their hypertension. Regarding self-efficacy, or the self-reported confidence in performing certain behaviors to controlling hypertension, those individuals who perceived themselves as having no self-efficacy had a lower level of education, compared to those who did perceive themselves as possessing self-efficacy. The findings of this study indicate that beliefs regarding hypertension and medical coverage are variables that need to be investigated further for individuals in the El Paso and Cuidad Juarez region. ^

Increasing awareness of colorectal cancer screening through targeted exam room based video messages

Colorectal cancer (CRC) is the third largest cause of cancer death in the United States. While the disease burden is high, there are proven methods to screen for CRC and detect it at a stage that is amenable to cure. Patients with low health literacy have difficulty navigating the health care system and are at increased risk to not receive preventive care services such as colorectal cancer screening (CRCS). To address this need, an exam-room based video was developed to be played for patients in the privacy of the exam room, while they are waiting to be seen by their medical provider. In roughly 2 minutes, the video informs the patient about CRC and CRCS and how they can successfully complete CRCS. One of the key barriers to completing CRCS is the need to increase patients' knowledge and improve attitudes surrounding CRCS. This study examines the impact of the video on patients' knowledge and attitudes about CRC and CRCS in a medically underserved patient population in Houston, Texas. ^ Sixty-one patients presenting for routine medical care were enrolled in the study. Depending on their randomization, the patients either received routine information about CRC and CRCS or they watched the video. We found that the patients who did watch the video did have improvements in their knowledge and improved attitudes about CRC and CRCS. Future studies will be needed to examine whether the video improves the patients' completion of CRCS.^

HPV knowledge, HPV vaccine awareness and initiation among Hispanics: The role of language, information seeking, and information scanning

Background. Among Hispanics, the HPV vaccine has the potential to eliminate disparities in cervical cancer incidence and mortality but only if optimal rates of vaccination are achieved. Media can be an important information source for increasing HPV knowledge and awareness of the vaccine. Very little is known about how media use among Hispanics affects their HPV knowledge and vaccine awareness. Even less is known about what differences exist in media use and information processing among English- and Spanish-speaking Hispanics.^ Aims. Examine the relationships between three health communication variables (media exposure, HPV-specific information scanning and seeking) and three HPV outcomes (knowledge, vaccine awareness and initiation) among English- and Spanish-speaking Hispanics.^ Methods. Cross-sectional data from a survey administered to Hispanic mothers in Dallas, Texas was used for univariate and multivariate logistic regression analyses. Sample used for analysis included 288 mothers of females aged 8-22 recruited from clinics and community events. Dependent variables of interest were HPV knowledge, HPV vaccine awareness and initiation. Independent variables were media exposure, HPV-specific information scanning and seeking. Language was tested as an effect modifier on the relationship between health communication variables and HPV outcomes.^ Results. English-speaking mothers reported more media exposure, HPV-specific information scanning and seeking than Spanish-speakers. Scanning for HPV information was associated with more HPV knowledge (OR = 4.26, 95% CI = 2.41 - 7.51), vaccine awareness (OR = 10.01, 95% CI = 5.43 - 18.47) and vaccine initiation (OR = 2.54, 95% CI = 1.09 - 5.91). Seeking HPV-specific information was associated with more knowledge (OR = 2.27, 95% CI = 1.23 - 4.16), awareness (OR = 6.60, 95% CI = 2.74 - 15.91) and initiation (OR = 4.93, 95% CI = 2.64 - 9.20). Language moderated the effect of information scanning and seeking on vaccine awareness.^ Discussion. Differences in information scanning and seeking behaviors among Hispanic subgroups have the potential to lead to disparities in vaccine awareness.^ Conclusion. Findings from this study underscore health communication differences among Hispanics and emphasize the need to target Spanish language media as well as English language media aimed at Hispanics to improve knowledge and awareness.^