THE ANALYSIS OF OVER-DISPERSED COUNT DATA FROM A SINGLE FACTOR STUDY

Methods for analyzing over-dispersed count data in a one-way layout were compared using a Monte Carlo study. Several variance stabilizing transformations were examined as alternatives to analyzing the raw data using a general linear model. Additionally, generalized linear models were fit using a log link. For the generalized linear model, three approaches to account for over-dispersion were investigated: (1) a negative binomial distribution with known k, (2) a Poisson distribution with Pearson\u27s X2 as an estimate of the scale parameter, and (3) a Poisson distribution with over-dispersion estimated using the deviance. The analysis of the raw data and log transformed data controlled the size of the tests better than the generalized linear models in the region of the sample space studied

Exploring disability from the perspective of adults living with HIV/AIDS: Development of a conceptual framework

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Results of an Environmental Scan to Determine the Level of Uncorrected Refractive Error in First Nations Elementary School Children in Ontario

A survey was developed and used to determine the level and quality of vision care services available to First Nations elementary school children across Ontario, and to indirectly determine the level of uncorrected refractive error in First Nations children. Overall, the total survey results showed that 1 child in 4 wore glasses. The results from the survey indicated that remote communities that had a visiting optometrist were more likely to have fewer cases of uncorrected refractive error than non-remote communities. The results suggest that in-community comprehensive eye exams delivered on a regular basis by visiting optometrists would be the most effective way of improving the vision and eye health status of First Nations children

Monitoring of Tumor Promotion and Progression in a Mouse Model of Inflammation-Induced Colon Cancer with Magnetic Resonance Colonography

AbstractEarly detection of precancerous tissue has significantly improved survival of most cancers including colorectal cancer (CRC). Animal models designed to study the early stages of cancer are valuable for identifying molecular events and response indicators that correlate with the onset of disease. The goal of this work was to investigate magnetic resonance (MR) colonography in a mouse model of CRC on a clinical MR imager. Mice treated with azoxymethane and dextran sulfate sodium were imaged by serial MR colonography (MRC) from initiation to euthanasia. Magnetic resonance colonography was obtained with both T1- and T2-weighted images after administration of a Fluorinert enema to remove residual luminal signal and intravenous contrast to enhance the colon wall. Individual tumor volumes were calculated and validated ex vivo. The Fluorinert enema provided a clear differentiation of the lumen of the colon from the mucosal lining. Inflammation was detected 3 days after dextran sulfate sodium exposure and subsided during the next week. Tumors as small as 1.2 mm3 were detected and as early as 29 days after initiation. Individual tumor growths were followed over time, and tumor volumes were measured by MR imaging correlated with volumes measured ex vivo. The use of a Fluorinert enema during MRC in mice is critical for differentiating mural processes from intraluminal debris. Magnetic resonance colonography with Fluorinert enema and intravenous contrast enhancement will be useful in the study of the initial stages of colon cancer and will reduce the number of animals needed for preclinical trials of prevention or intervention

How do existing HIV-specific instruments measure up? Evaluating the ability of instruments to describe disability experienced by adults living with HIV

Background: Despite the multitude of health challenges faced by adults living with HIV, we know of no HIV-specific instrument developed for the purpose of describing the health-related consequences of HIV, a concept known as disability. In a previous phase of research, adults living with HIV conceptualized disability as symptoms/ impairments, difficulties carrying out day-to-day activities, challenges to social inclusion, and uncertainty that may fluctuate on a daily basis and over the course of living with HIV. In this paper, we describe the extent to which existing HIV-specific health-status instruments capture the experience of disability for adults living with HIV. Methods: We searched databases from 1980 to 2006 for English language, HIV-specific, self-reported questionnaires consisting of at least two items that were tested for reliability and validity. We then conducted a content analysis to assess how well existing questionnaires describe disability as defined by the Episodic Disability Framework, a framework that conceptualizes this experience from the perspective of adults living with HIV. We matched items of the instruments with categories of the framework to evaluate the extent to which the instruments capture major dimensions of disability in the framework. Results: We reviewed 4274 abstracts, of which 30 instruments met the inclusion criteria and were retrieved. Of the four major dimensions of disability, symptoms/impairments were included in all 30 instruments, difficulties with day-to-day activities in 16, challenges to social inclusion in 16, and uncertainty in 9. Seven instruments contained at least 1 item from all 4 dimensions of disability (breadth) however, the comprehensiveness with which the dimensions were represented (depth) varied among the instruments. Conclusions: In general, symptoms/impairments and difficulties carrying out day-to-day activities were the disability dimensions characterized in greatest depth while uncertainty and challenges to social inclusion were less well represented. Although none of the instruments described the full breadth and depth of disability as conceptualized by the Episodic Disability Framework, they provide a foundation from which to build a measure of disability for adults living with HIV

“The First Day He Kicked Shoes at Me, the Last Day He Brought Me a Picture of Himself”: Investigating the Practicum Experiences of Pre-service Teachers

The purpose of this study was to describe the ways in which the experiences gained during practica influence the developing self-efficacy of Canadian pre-service teachers for teaching in inclusive classrooms. Questionnaires were issued to participants in teacher education programs at 11 universities across Canada, and the data were subjected to content analysis. Several themes that emerged from the participant responses were found to be influential in pre-service teachers’ feelings of efficacy, with behaviour management having the greatest influence, regardless of whether participants felt successful or challenged. Academic outcomes, relationships with students, and other school adults as resources were also identified as themes influencing pre-service teachers’ feelings of success and challenge in practica. The data revealed attitudes and beliefs about inclusion and the impact these may have on teacher efficacy. Several elements can positively influence teacher efficacy including the ability to identify and utilize instructional and personnel resources, the ability to form supportive professional relationships with other school adults, and the ability to recognize achievement as it pertains to the individual rather than prescribed norms. As beliefs about self-efficacy are informed by enactive mastery experiences, vicarious experiences, physiological factors, and verbal persuasion, teacher preparation programs can foster teacher efficacy by encouraging the development of positive attitudes and equipping teachers with the skills they need