Clinical Severity of Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant Relative to Delta in British Columbia, Canada: A Retrospective Analysis of Whole-Genome Sequenced Cases.

Background: In late 2021, the Omicron severe acute respiratory syndrome coronavirus 2 variant emerged and rapidly replaced Delta as the dominant variant. The increased transmissibility of Omicron led to surges in case rates and hospitalizations; however, the true severity of the variant remained unclear. We aimed to provide robust estimates of Omicron severity relative to Delta.

The State of Heart Failure Care in Canada: Minimal Improvement in Readmissions Over Time Despite an Increased Number of Evidence-Based Therapies.

Background: An unanswered question is whether the combination of advances in medical and device therapy over the past decade has translated into improved outcomes for patients with heart failure (HF) in Canada.

Methods: The Canadian Institute for Health Information (CIHI) Hospital Morbidity Database was used to identify hospitalizations for HF among patients aged 18 years and older in Canadian hospitals during fiscal years 2009/2010 and 2018/2019. We assessed interprovincial differences in age, sex, length of stay (LOS), discharge disposition, type of admitting hospital, and most responsible service, for all HF admissions.

Opioid use after outpatient elective general surgery: quantifying the burden of persistent use.

Purpose: Surgery is a major risk factor for chronic opioid use among patients who had not recently been prescribed opioids. This study identifies the rate of, and risk factors for, persistent opioid use following laparoscopic cholecystectomy and open inguinal hernia repair in patients not recently prescribed opioids.

Methods: This retrospective population-based cohort study included all patients who had not been prescribed opioids in the 6 months prior to undergoing open inguinal hernia repair or laparoscopic cholecystectomy from January 2013 to July 2016 in Ontario.

Comparing the predictive accuracy of frailty instruments applied to preoperative electronic health data for adults undergoing noncardiac surgery.

Background: Preoperative frailty is associated with increased risk of postoperative mortality and complications. Routine preoperative frailty assessment is underperformed. Automation of preoperative frailty assessment using electronic health data could improve adherence to guideline-based care if an accurate instrument is identified.

Concussion Public Policy in Elementary and High Schools in Ontario, Canada: A Cross-Sectional Survey to Examine Implementation Compliance, Barriers, and Facilitators.

Background: Concussion public policies have been developed to address the burden of concussions. The aim of the present study was to examine implementation compliance, barriers, and facilitators of Canada's first concussion public policy, Ontario's Policy/Program Memorandum 158: School Board Policies on Concussion (PPM158).

Methods: An electronic survey was sent to 515 randomly selected elementary and high school principals across specific geographic, language, and publicly funded school types in Ontario.

Home to Stay: A randomized controlled trial protocol to assess use of a mobile app to reduce readmissions following colorectal surgery.

Aim: Patients undergoing colorectal surgery face high rates of emergency room visits and readmission to hospital. These unplanned hospital visits lead to both increased patient anxiety and health care costs. The aim of this study is to evaluate the use of mobile application to support patients undergoing colorectal surgery following discharge from hospital.

Primary Care Physician Use and Frequency of Visits Among Physicians in Ontario, Canada.

Importance: Maintaining a healthy physician workforce includes the routine use of primary care physician (PCP) services; however, physicians may face barriers to attaining formal care.

Objective: To analyze access to and frequency of visits to PCPs among physicians compared with nonphysicians.

Design, Setting, And Participants: This population-based, retrospective cohort study used registration data from the College of Physicians and Surgeons of Ontario, Canada, from January 1, 1990, to March 31, 2018.

Increased demand for paramedic transports to the emergency department in Ontario, Canada: a population-level descriptive study from 2010 to 2019.

Purpose: We examined changes in annual paramedic transport incidence over the ten years prior to COVID-19 in comparison to increases in population growth and emergency department (ED) visitation by walk-in.

Methods: We conducted a population-level cohort study using the National Ambulatory Care Reporting System from January 1, 2010 to December 31, 2019 in Ontario, Canada. We included all patients triaged in the ED who arrived by either paramedic transport or walk-in.

Perinatal mental illness among women with disabilities: a population-based cohort study.

Purpose: To examine the risk of perinatal mental illness, including new-onset disorders and recurrent or ongoing use of mental health care, comparing women with physical, sensory, intellectual/developmental, and multiple disabilities to those without a disability.

Methods: From all women aged 15-49 years with a singleton birth in Ontario, Canada (2003-2018), those with physical (n = 144,972), sensory (n = 45,249), intellectual/developmental (n = 2,227), and ≥ 2 of these disabilities ("multiple disabilities"; n = 8,883), were compared to 1,601,363 without a disability on risk of healthcare system contact for mental illness from conception to 365 days postpartum. The cohort was stratified into: (1) no pre-pregnancy mental illness (to identify new-onset illness), (2) distal mental illness (> 2 years pre-pregnancy, to identify recurrent illness), and (3) recent mental illness (0-2 years pre-pregnancy, to identify ongoing contact).

Screening Accuracy of the 50 g-Glucose Challenge Test in Twin Compared With Singleton Pregnancies.

Context: The optimal 50 g-glucose challenge test (GCT) cutoff for the diagnosis of gestational diabetes mellitus (GDM) in twin pregnancies is unknown.

Objective: This work aimed to explore the screening accuracy of the 50 g-GCT and its correlation with the risk of large for gestational age (LGA) newborn in twin compared to singleton pregnancies. A population-based retrospective cohort study (2007-2017) was conducted in Ontario, Canada.

The Association Between Telemedicine Use and Changes in Health Care Usage and Outcomes in Patients With Congestive Heart Failure: Retrospective Cohort Study.

Background: Telemedicine use has become widespread owing to the COVID-19 pandemic, but its impact on patient outcomes remains unclear.

Objective: We sought to investigate the effect of telemedicine use on changes in health care usage and clinical outcomes in patients diagnosed with congestive heart failure (CHF).

Methods: We conducted a population-based retrospective cohort study using administrative data in Ontario, Canada.

Concurrent external validation of bloodstream infection probability models.

Objective: Accurately estimating the likelihood of bloodstream infection (BSI) can help clinicians make diagnostic and therapeutic decisions. Many multivariate models predicting BSI probability have been published. This study measured the performance of BSI probability models within the same patient sample.

Comparison of machine learning and the regression-based EHMRG model for predicting early mortality in acute heart failure.

Background: Although risk stratification of patients with acute decompensated heart failure (HF) is important, it is unknown whether machine learning (ML) or conventional statistical models are optimal. We developed ML algorithms to predict 7-day and 30-day mortality in patients with acute HF and compared these with an existing logistic regression model at the same timepoints.

Methods: Patients presenting to one of 86 hospitals, who were either admitted to hospital or discharged home directly from the emergency department, were randomly selected using stratified random sampling.

Validation of a natural language processing algorithm to identify adenomas and measure adenoma detection rates across a health system: a population-level study.

Background And Aims: Measuring adenoma detection rates (ADRs) at the population level is challenging because pathology reports are often reported in an unstructured format; further, there is significant variation in reporting methods across institutions. Natural language processing (NLP) can be used to extract relevant information from text-based records. We aimed to develop and validate an NLP algorithm to identify colorectal adenomas that could be used to report ADR at the population level in Ontario, Canada.

Characterizing people with frequent emergency department visits and substance use: a retrospective cohort study of linked administrative data in Ontario, Alberta, and B.C., Canada.

Background: Substance use is common among people who visit emergency departments (EDs) frequently. We aimed to characterize subgroups within this cohort to better understand care needs/gaps, and generalizability of characteristics in three Canadian provinces.

Methods: This was a retrospective cohort study (April 1, 2013 to March 31, 2016) of ED patients in Ontario, Alberta, and British Columbia (B.

Body Weight at Age Four Years and Readiness to Start School: A Prospective Cohort Study.

Adolescents with obesity have lower academic performance, but little is known about the association between body weight in early childhood and school readiness. The objective was to examine the association between age- and sex-standardized body mass index (zBMI) and body weight status and school readiness in young children. A prospective cohort study in Toronto, Canada, was conducted in young children enrolled in TARGet Kids!.

Patient-Proxy and Societal Perspectives of Quality-of-Life Utilities in Children With Cleft Lip and Palate Managed With Surgical Repair vs No Repair in Ethiopia.

Importance: In Ethiopia, more than 70% of infants with cleft lip and/or palate (CL/P) lack access to surgery. Infants who are untreated can experience severe malnutrition and extreme social stigma resulting in abandonment. Utilities are standardized measures of health-related quality of life (HRQOL) that inform health care resource allocation.

Ontario Cataract Quality Outcome Initiative: appropriateness and prioritization of cataract surgery.

Objective: To explore the utility of the Catquest 9SF visual function (VF) questionnaire along with visual acuity (VA) for determining appropriateness and priority for cataract surgery. To evaluate the feasibility of administering the Catquest-9SF in a clinical setting using web-based electronic data capture and interpretation.

Design: Prospective multicentred interventional observational study.

Prediction models of diabetes complications: a scoping review.

Background: Diabetes often places a large burden on people with diabetes (hereafter 'patients') and the society, that is, in part attributable to its complications. However, evidence from models predicting diabetes complications in patients remains unclear. With the collaboration of patient partners, we aimed to describe existing prediction models of physical and mental health complications of diabetes.

Cannabis use and risks of respiratory and all-cause morbidity and mortality: a population-based, data-linkage, cohort study.

Introduction: Although cannabis is frequently used worldwide, its impact on respiratory health is characterised by controversy.

Objective: To evaluate the association between cannabis use and respiratory-related emergency room (ER) visits and hospitalisations.

Methods: A retrospective, population-based, cohort study was carried out, linking health survey and health administrative data for residents of Ontario, Canada, aged 12-65 years, between January 2009 and December 2015.

Automated Movement Analysis to Predict Cerebral Palsy in Very Preterm Infants: An Ambispective Cohort Study.

The General Movements Assessment requires extensive training. As an alternative, a novel automated movement analysis was developed and validated in preterm infants. Infants < 31 weeks’ gestational age or birthweight ≤ 1500 g evaluated at 3−5 months using the general movements assessment were included in this ambispective cohort study.

Long-term exposure to fine particulate matter and ozone and the onset of systemic autoimmune rheumatic diseases: an open cohort study in Quebec, Canada.

Objectives: To estimate associations between fine particulate matter (PM) and ozone and the onset of systemic autoimmune rheumatic diseases (SARDs).

Methods: An open cohort of over 6 million adults was constructed from provincial physician billing and hospitalization records between 2000 and 2013. We defined incident SARD cases (SLE, Sjogren's syndrome, scleroderma, polymyositis, dermatomyositis, polyarteritis nodosa and related conditions, polymyalgia rheumatic, other necrotizing vasculopathies, and undifferentiated connective tissue disease) based on at least two relevant billing diagnostic codes (within 2 years, with at least 1 billing from a rheumatologist), or at least one relevant hospitalization diagnostic code.