Fixed Size Confidence Regions for the Parameters of the Mixed Effects Logistic Regression Model

We develop fixed size confidence regions for estimating the fixed and random effects parameters of the mixed effects logistic regression model. This model applies to, among others, the study of the effects of covariates on a dichotomous response variable when subjects are sampled in clusters. Two sequential procedures are developed to estimate with a prescribed accuracy (confidence level) and fixed precision the set of fixed and random effects parameters and linear transformations of these parameters, respectively. We show that the two procedures are asymptotically consistent (i.e., the coverage probability converges to the nominal confidence level) and asymptotically efficient (i.e., the ratio of the expected random sample size to the unknown best fixed sample size converges to 1) as the width of the confidence region converges to 0. Suggestions to improve the performance of the procedures are provided based on Monte Carlo simulation and illustrated through a longitudinal clinical trial data

Impact of Skills for Change Program on metabolic control, diet and physical activity levels in adults with type 2 diabetes: A cluster randomized trial

Background: Type 2 diabetes mellitus is highly prevalent in the Arab Gulf countries. Despite this, limited culturally-adapted lifestyle intervention studies have been conducted in this region. Methods: In this culturally adapted 12-month cluster randomized trial, 382 patients with type 2 diabetes, aged 20–70 years were recruited from 6 public healthcare centers (3 interventions and 3 controls) in Al Ain, United Arab Emirates. The primary outcome of this study was a change in hemoglobin A1c (HbA1c). The secondary outcomes were Body Mass Index (BMI), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, total cholesterol, dietary intake, and physical activity levels. A diet and physical activity intervention, guided by the social cognitive theory, was delivered individually and in group format to the intervention group. The control group continued receiving only their usual diabetes management care. The data were collected at baseline and 1 year after participation. Results: The mean baseline HbA1c levels of the control and the intervention groups were 7.45 ± 0.11% and 7.81 ± 0.11%, respectively. At the end of the 12-month intervention, there was no significant difference in the changes of mean HbA1c between the intervention and the control groups. On the other hand, BMI and daily caloric intake were significantly decreased in the intervention compared to the control group by 1.18 kg/m2 (95% CI: -1.78 − -0.60) and 246 kcal (95% CI: -419.52 − -77.21), respectively, after controlling for age, gender, education, marital status, duration since diabetes diagnosis, diabetes treatment, treatment clinic, and baseline values. Sitting time during the week-end was significantly lower, difference 52.53 minutes (95% CI: 93.93 − -11.14). Conclusions: This community-based lifestyle intervention for patients with baseline HbA1c <8% did not result in a significant decrease of HbA1c but reduced caloric intake, body weight, and weekend inactivity after controlling for the covariates. Trial registration: This trial was registered on February 11, 2020 with Clinicaltrials.gov (NCT04264793)

Effects of Diabetes Prevention Education Program for Overweight and Obese Subjects with a Family History of Type 2 Diabetes Mellitus: A Pilot Study from the United Arab Emirates

Objectives: The association of obesity and family history of type 2 diabetes mellitus (T2DM) provides an opportunity for risk stratification and prevention, as these two conditions are the most well-known risk factors for T2DM. We aimed to test the feasibility and effects of a diabetes mellitus prevention education program designed for overweight and obese Emirati people with at least one parent with T2DM. Methods: We conducted a pilot study using a pre-post design without a control arm at the Diabetes Center at Tawam Hospital in Al Ain, UAE. Overweight and obese subjects with at least one parent with T2DM were invited to participate. Three study assessments were conducted at baseline, three months, and six months including a questionnaire, anthropometry, and laboratory assessments. Interventions included three individualized or family-engaged counseling sessions based on the DiAlert protocol. The study outcomes included awareness of risks and prevention opportunities to T2DM, behavior changes in nutrition and exercise, decreased waist-circumference, and clinical/metabolic/inflammatory markers. Pre-post changes were analyzed using repeated-measures analysis of variance. Results: One hundred twenty-two overweight or obese individuals were approached. Forty-four individuals met the eligibility criteria, and 32 individuals (35.0±9.0 years; 75.0% female) completed the study. At six months, there were significant improvements in the glycated hemoglobin levels (p = 0.007), high-density lipoprotein (p < 0.049), serum creatinine (p < 0.025), estimated glomerular filtration rate (p = 0.009), and adiponectin levels (p < 0.024). Sixteen of 32 participants had ≥ 2 cm reduction in waist circumference. They demonstrated notable physical and laboratory improvements in moderate-vigorous activity, average activity counts per day, tumor necrosis factor-alpha, and interleukin-6 total cholesterol, triglyceride, and low-density lipoprotein. Conclusions: Offering family-oriented diabetes education to people at risk for T2DM is well received and has favorable effects on relevant risk factors. Better testing with large-scale randomized controlled studies is needed, and implementing similar educational programs for the Emirati population seems warranted

Indoor Air Pollutants and Health in the United Arab Emirates

Background: Comprehensive global data on the health effects of indoor air pollutants are lacking. There are few large population-based multi–air pollutant health assessments. Further, little is known about indoor air health risks in the Middle East, especially in countries undergoing rapid economic development

Epidemiology of severe pediatric adenovirus lower respiratory tract infections in Manitoba, Canada, 1991-2005

<p>Abstract</p> <p>Background</p> <p>Most pediatric adenovirus respiratory infections are mild and indistinguishable from other viral causes. However, in a few children, the disease can be severe and result in substantial morbidity. We describe the epidemiologic, clinical, radiologic features and outcome of adenovirus lower respiratory tract infections (LRTI) in Aboriginal and Non-Aboriginal children in Manitoba, Canada during the years 1991 and 2005.</p> <p>Methods</p> <p>This was a retrospective study of 193 children who presented to the department of pediatrics at Winnipeg Children's Hospital, Manitoba, Canada with LRTI and had a positive respiratory culture for adenovirus. Patients' demographics, clinical and radiologic features and outcomes were collected. Adenovirus serotype distributions and temporal associations were described. Approximate incidence comparisons (detection rates) of adenovirus LRTI among Aboriginal and Non-Aboriginal children were estimated with 95% confidence intervals.</p> <p>Results</p> <p>Adenovirus infections occurred throughout the year with clusters in the fall and winter. Serotypes 1 to 3 were the predominant isolates (two thirds of the cases). The infection was more frequent among Canadian Aboriginals, as illustrated in 2004, where its incidence in children 0-4 years old was 5.6 fold higher in Aboriginals (13.51 vs. 2.39 per 10,000, <it>p </it>< 0.000). There were no significant differences in length of hospitalization and use of ventilator assistance between the two groups (<it>p </it>> 0.185 and <it>p </it>> 0.624, respectively) nor across serotypes (<it>p </it>> 0.10 and <it>p </it>> 0.05, respectively). The disease primarily affected infants (median age, 9.5 months). Most children presented with bronchiolitis or pneumonia, with multi-lobar consolidations on the chest x-ray. Chronic (residual) changes were documented in 16 patients, with eight patients showing bronchiectasis on the chest computerized tomography scan.</p> <p>Conclusions</p> <p>Adenovirus infection is associated with significant respiratory morbidities, especially in young infants. The infection appears to be more frequent in Aboriginal children. These results justify a careful follow-up for children with adenovirus LRTI.</p

Sequential tests for clinical trials of two treatments with bounded deficiency.

In a clinical trial of two treatments, one goal of the experimenter is to design an experiment such that the number of patients assigned to the inferior treatment is minimized. A Bayesian formulation for this problem is studied. Treatment outcomes are assumed to be independent and normally distributed, with conjugate priors. The analysis is conducted in a large sample limit where sampling costs are scaled to zero. First we show there is little harm restricting attention to procedures that stop according to Kiefer and Sacks stopping rule. There are procedures in this class with risks that exceed the minimum Bayes risk by the cost of a fixed number of observations. Using this we then develop procedures with bounded deficiency. A Monte Carlo study shows that these procedures perform better than the pairwise procedure.Ph.D.Pure SciencesStatisticsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/128296/2/8907179.pd

Nutrition Knowledge and Satisfaction Levels of Postbariatric Surgery Adults in the United Arab Emirates: A Pilot Study

Research assessing the nutrition knowledge of postbariatric surgery patients is limited, although this category of patients is predisposed to malnutrition. In this pilot study, we explored postbariatric nutrition knowledge, satisfaction levels with dietitian nutrition counseling, and decision to undergo bariatric surgery of 83 patients who attended a postbariatric outpatient nutrition clinic in Dubai, United Arab Emirates (UAE). A cross-sectional design involving gender-stratified random sampling method was used to recruit 83 postbariatric surgery participants. A self-administered questionnaire was employed to collect information about nutrition knowledge related to dietary recommendations after bariatric surgery as well as participant views on dietitian nutrition counseling, their decision to undergo bariatric surgery, and nutrition-related complications experienced after the surgery. The mean (SD) knowledge score of postbariatric diet was 9.7 (2.05) out of a maximum possible score of 14. The majority of the participants (78.3%) correctly identified which foods are recommended during the first stage of the postbariatric surgery diet, and more than 90% knew about the importance of high-protein supplements after bariatric surgery. Female participants had significantly higher mean knowledge score compared to males (p=0.02). Although nearly 80% of the participants reported regular follow-up with their dietitian, only 10.8% reported high adherence to the dietitian’s instructions. Moreover, more than two-thirds of the participants (71.1%) rated dietary advice provided by dietitians as vague. The most common complication experienced by the participants after bariatric surgery was nausea (61.4%). Furthermore, the majority of the participants (83.4%) found their daily and leisure activities to be more enjoyable after bariatric surgery. Ways of improving the quality of information delivery by dietitians should be explored to enhance patient comprehension and adherence to postbariatric surgery diet recommendations. Future research involving a larger and more representative sample to extend our findings are needed