Clinical Epidemiology Commons^™

Developing Artificial Intelligence And Machine Learning To Support Primary Care Research And Practice, Jacqueline K. Kueper

Electronic Thesis and Dissertation Repository

This thesis was motivated by the potential to use "everyday data", especially that collected in electronic health records (EHRs) as part of healthcare delivery, to improve primary care for clients facing complex clinical and/or social situations. Artificial intelligence (AI) techniques can identify patterns or make predictions with these data, producing information to learn about and inform care delivery. Our first objective was to understand and critique the body of literature on AI and primary care. This was achieved through a scoping review wherein we found the field was at an early stage of maturity, primarily focused on clinical decision support …

Spin And Distortion In Surgical Trials, Andrea Mataruga

Electronic Thesis and Dissertation Repository

Research problem: Randomized controlled trials (RCTs) are essential; however, their validity can be threatened through distortion or spin. This study quantifies publication bias and distorted outcome reporting.

Methodology: All surgical RCTs registered on ClinicalTrials.gov from 1997-2017 were identified and a sample was obtained through random and intentional selection. Failure to publish (proportion of studies that remain unpublished), outcome distortion (changing intended outcomes), and spin (distorted presentation) were explored. Comparisons were made for positive versus negative studies and for high-income (HICs) versus low-middle income countries (LMICs).

Results: In total, 13,761 RCTs were registered (median enrollment size = 96, 94% from …

Predicting Important Patient-Reported Outcomes For Glaucoma Management: Cross-Sectional Study, Lavanya Uruthiramoorthy

Electronic Thesis and Dissertation Repository

The initiative to understand patient-reported outcomes (PROs) has increased to improve glaucoma management. We sought to identify important predictors of four PROs: social support and community integration, presence of depressive symptoms, vision-related quality of life (VRQoL) and preference-based Health-Related quality of life (HRQoL). A cross-sectional study was conducted among patients in London, Ontario (n=250). Regression models, and classification and regression trees were built. Leave-one-out cross-validation assessed the models’ predictive performance. Mobility aid use, best corrected visual acuity (BCVA), income and living arrangements were predictors identified for VRQoL, and social support and community integration. Mobility aid use was also predictive of …

Reducing Distortion – Identifying Areas To Improve The Quality Of Randomized Clinical Trials Published In Anesthesiology Journals, Jeffrey T.Y. Chow

Electronic Thesis and Dissertation Repository

Randomized clinical trials (RCTs) provide important evidence to inform clinical decision making; if these trials are of low quality, the resulting clinical decision will likely also be of low quality. The main purpose of this thesis was to conduct a series of methodological surveys that would identify potential areas of improvement in the quality of reporting for RCTs published in anesthesiology journals. Trial registration adequacy, adherence to CONSORT for Abstracts guidelines, and sample size calculation quality were all assessed, with a final chapter exploring the effect of industry funding on these methodological quality measures. While the results suggest improvement over …

Physical Exertion As A Risk Factor For Ventricular Arrhythmia: A Prospective Cohort Study, Harpreet S. Chahal

Electronic Thesis and Dissertation Repository

Episodes of physical exertion are associated with an immediately higher risk of cardiovascular events while physical activity over the long-term is cardioprotective. To assess the transient and long-term risk of ventricular arrhythmia (VA), we conducted a nested case-crossover study within a prospective cohort of 97 patients with implantable cardioverter-defibrillators (ICD). Within an hour of episodes of exertion, the risk of VA was 5.3 (95% CI 2.7 – 10.6) times greater compared to periods of rest. The association was higher among patients with aerobic fitness below the median (RR[relative risk]=17.5, 95% 5.2 – 58.5) than for patients with aerobic fitness above …

Patency And Complication Rates Of The Arteriovenous Fistula: A Systematic Review, Ahmed A. Al-Jaishi

Electronic Thesis and Dissertation Repository

Advantages of fistulas, which include long patency and low complication rates, were ascertained over two decades ago and may not apply to the contemporary dialysis population. We conducted a systematic review to summarize the patency and complication rates of fistulas from literature published after 1999. We screened 7,008 citations and 62 articles met our criteria. The risk of primary failure was 27% (95% confidence interval (CI): 23–32%). When primary failures were included, the primary and secondary patency rates were 59% (CI 53–64%) and 66% (CI 58–74%) at one year, respectively. The median rates of infection, ischemic steal syndrome, and thrombosis …