Publications by authors named "Michelle Greiver"

Introduction: SARS-CoV-2 is now endemic and expected to remain a health threat, with new variants continuing to emerge and the potential for vaccines to become less effective. While effective vaccines and natural immunity have significantly reduced hospitalisations and the need for critical care, outpatient treatment options remain limited, and real-world evidence on their clinical and cost-effectiveness is lacking. In this paper, we present the design of the Canadian Adaptive Platform Trial of Treatments for COVID in Community Settings (CanTreatCOVID).

View Article and Find Full Text PDF

Background: Chronic pain (CP) often co-occurs with depression, but promising scalable interventions have been under-investigated. We assessed the effectiveness of the virtually-delivered Sahaj Samadhi Meditation (SSM) program in reducing depressive symptoms in people with CP and moderate depressive symptoms.

Methods: We conducted a randomized controlled trial comparing SSM to the Health Enhancement Program (HEP), an active control.

View Article and Find Full Text PDF

Treatment-confounder feedback is present in time-to-recurrent or longitudinal event analysis when time-dependent confounders are themselves influenced by previous treatments. Conventional models produce misleading statistical inference of causal effects due to conditioning on these factors on the causal pathway. Marginal structural models are often applied to quantify the causal treatment effect, estimated using longitudinal weights that mimic the randomization procedure by balancing the covariate distributions across the treatment groups.

View Article and Find Full Text PDF

Importance: Whether administration of blood pressure medications at bedtime instead of in the morning reduces cardiovascular risk is unknown, as findings from large clinical trials have not been consistent. There is also concern that bedtime antihypertensive use could induce glaucoma-related visual loss or other hypotensive/ischemic adverse effects.

Objective: To determine the effect of bedtime vs morning administration of antihypertensive medications on major cardiovascular events and death.

View Article and Find Full Text PDF

Objectives: The impact of concurrent adherence to antihypertensives, antidiabetics, and statins on cardiovascular disease (CVD) outcomes and intermediate clinical outcomes in people with hypertension and diabetes remains unclear. This study aimed to evaluate the association between medication adherence and CVD outcomes in such patients.

Methods: This retrospective cohort study analyzed the electronic medical records of 36,211 adults aged 18 or older diagnosed with hypertension and diabetes between January 2008 and June 2016 in Canada.

View Article and Find Full Text PDF

Chronic kidney disease (CKD) affects over 13% of the population, totaling more than 800 million individuals worldwide. Timely identification and intervention are crucial to delay CKD progression and improve patient outcomes. This research focuses on developing a predictive model to classify diabetic patients showing signs of kidney function impairment based on their CKD development risk.

View Article and Find Full Text PDF

Background: There is an increasing prevalence of multiple conditions (multimorbidity) and multiple medications (polypharmacy) across many populations. Previous literature has focused on the prevalence and impact of these health states separately, but there is a need to better understand their co-occurrence.

Methods And Findings: This study reported on multimorbidity and polypharmacy among middle-aged and older adults in two national datasets: the Canadian Longitudinal Study on Aging (CLSA) and the Canadian Primary Care Sentinel Surveillance Network (CPCSSN).

View Article and Find Full Text PDF

Objectives: Sodium-glucose cotransporter-2 inhibitors (SGLT2is) provide heart and kidney benefits in adults with diabetes and cardiovascular disease (CVD). Public drug coverage policies for SGLT2is differ by province in Canada. In this study, we describe the potential effects of prior authorization/step therapy (PA/ST) and relatively high income-based deductibles, compared with regular benefit status with modest copay, on SGLT2i prescriptions in high-risk adults.

View Article and Find Full Text PDF

Background: Unnecessary antibiotic prescriptions in primary care are common and contribute to antimicrobial resistance in the population. Audit and feedback (A&F) on antibiotic prescribing to primary care can improve the appropriateness of antibiotic prescribing, but the optimal approach is uncertain. We performed two pragmatic randomized controlled trials of different approaches to audit and feedback.

View Article and Find Full Text PDF

Background: The impact of social frailty on older adults is profound including mortality risk, functional decline, falls, and disability. However, effective strategies that respond to the needs of socially frail older adults are lacking and few studies have unpacked how social determinants operate or how interventions can be adapted during periods requiring social distancing and isolation such as the COVID-19 pandemic. To address these gaps, we conducted a scoping review using JBI methodology to identify interventions that have the best potential to help socially frail older adults (age ≥65 years).

View Article and Find Full Text PDF

Background: Higher numbers of family physicians (FPs) stopped practicing or retired during the COVID-19 pandemic, worsening the family doctor shortage in Canada. Our study objective was to determine which factors were associated with FPs' plans to retire earlier during the COVID-19 pandemic.

Methods: We administered two cross-sectional online surveys to Ontario FPs asking whether they were "planning to retire earlier" as a result of the pandemic during the first and third COVID-19 pandemic waves (Apr-Jun 2020 and Mar-Jul 2021).

View Article and Find Full Text PDF

Introduction: Around the world, many organisations are working on ways to increase the use, sharing, and reuse of person-level data for research, evaluation, planning, and innovation while ensuring that data are secure and privacy is protected. As a contribution to broader efforts to improve data governance and management, in 2020 members of our team published 12 minimum specification essential requirements (min specs) to provide practical guidance for organisations establishing or operating data trusts and other forms of data infrastructure.

Approach And Aims: We convened an international team, consisting mostly of participants from Canada and the United States of America, to test and refine the original 12 min specs.

View Article and Find Full Text PDF

Background: There has been conflicting evidence on the association between multimorbidity and blood pressure (BP) control. This study aimed to investigate this associations in people with hypertension attending primary care in Canada, and to assess whether individual long-term conditions are associated with BP control.

Methods: This was a cross-sectional study in people with hypertension attending primary care in Toronto between January 1, 2017 and December 31, 2019.

View Article and Find Full Text PDF

Importance: Breast cancer screening with mammography is recommended in Ontario, Canada, for females 50 years or older. Females with schizophrenia are at higher risk of breast cancer, but in Ontario it is currently unknown whether breast cancer screening completion differs between those with vs without schizophrenia and whether primary care payment models are a factor.

Objective: To compare breast cancer screening completion within 2 years after the 50th birthday among females with and without schizophrenia, and to identify the association between breast cancer screening completion and different primary care payment models.

View Article and Find Full Text PDF

Background: Audit and feedback (A&F), the summary and provision of clinical performance data, is a common quality improvement strategy. Successful design and implementation of A&F-or any quality improvement strategy-should incorporate evidence-informed best practices as well as context-specific end user input.

Objective: We used A&F theory and user-centered design to inform the development of a web-based primary care A&F dashboard.

View Article and Find Full Text PDF

Background: Topic models are a class of unsupervised machine learning models, which facilitate summarization, browsing and retrieval from large unstructured document collections. This study reviews several methods for assessing the quality of unsupervised topic models estimated using non-negative matrix factorization. Techniques for topic model validation have been developed across disparate fields.

View Article and Find Full Text PDF

Objectives: We sought to validate, or refute, the common belief that bedtime diuretics are poorly tolerated due to nocturia.

Design: Prespecified prospective cohort analysis embedded within the randomised BedMed trial, in which hypertensive participants are randomised to morning versus bedtime antihypertensive administration.

Setting: 352 community family practices across 4 Canadian provinces between March 2017 and September 2020.

View Article and Find Full Text PDF

Introduction: Measuring the performance of interprofessional primary care is needed to examine whether this model of care is achieving its desired outcomes on patient care and health system effectiveness as well as to guide quality improvement initiatives. The aim of this scoping review is to map the literature on primary care performance measurement indicators to determine the extent to which current indicators capture or could be adapted to capture processes, outputs and outcomes that reflect interprofessional primary care.

Methods And Analysis: The review will be guided by the six-stage framework by Arksey and O'Malley (2005).

View Article and Find Full Text PDF

Background: Clinical guidelines for most adults with diabetes recommend maintaining hemoglobin A (HbA) levels ≤7% (≤53 mmol/mol) to avoid microvascular and macrovascular complications. People with diabetes of different ages, sexes, and socioeconomic statuses may differ in their ease of attaining this goal.

Objective: As a team of people with diabetes, researchers, and health professionals, we aimed to explore patterns in HbA results among people with type 1 or type 2 diabetes in Canada.

View Article and Find Full Text PDF

Context: More than 25% of Canadian seniors are prescribed 10+ different medications each year. There is a direct association between more medications and persistent high care needs/costs for seniors. Effective and appropriate deprescribing for seniors in primary care is needed.

View Article and Find Full Text PDF

The objective of this study was to investigate whether a rule-based natural language processing (NLP) system, applied to primary care clinical text data, could be used to monitor COVID-19 viral activity in Toronto, Canada. We employed a retrospective cohort design. We included primary care patients with a clinical encounter between January 1, 2020 and December 31, 2020 at one of 44 participating clinical sites.

View Article and Find Full Text PDF

Unsupervised topic models are often used to facilitate improved understanding of large unstructured clinical text datasets. In this study we investigated how ICD-9 diagnostic codes, collected alongside clinical text data, could be used to establish concurrent-, convergent- and discriminant-validity of learned topic models. Retrospective open cohort design.

View Article and Find Full Text PDF

Substantial effort has been dedicated to conducting randomized controlled experiments to generate clinical evidence for diabetes treatment. Randomized controlled experiments are the gold standard for establishing cause and effect. However, due to their high cost and time commitment, large observational databases such as those comprised of electronic health record (EHR) data collected in routine primary care may provide an alternative source with which to address such causal objectives.

View Article and Find Full Text PDF