Andrew Calzavara
YOU?
Author Swipe
View article: COVID-related delays in non-urgent adult surgeries: comparing population-based results from two Canadian provinces
COVID-related delays in non-urgent adult surgeries: comparing population-based results from two Canadian provinces Open
Background During the COVID-19 pandemic, non-urgent surgeries were delayed in order to increase the capacity to care for patients with COVID-19. To shed light on the effect of pandemic-related surgical ramp down on the quality of surgical …
View article: Emergency Department Use Prior to Cancer Diagnosis and Mortality
Emergency Department Use Prior to Cancer Diagnosis and Mortality Open
Importance The emergency department (ED) is a common yet understudied route to cancer diagnosis. It has been reported that over 1 in 3 patients in Ontario, Canada, used the ED prior to cancer diagnosis. Objective To examine the association…
View article: Outcomes and factors influencing survival in patients with diffuse large B-cell lymphoma: a population-based analysis
Outcomes and factors influencing survival in patients with diffuse large B-cell lymphoma: a population-based analysis Open
Given the rapidly evolving treatment landscape for diffuse large B-cell lymphoma (DLBCL), we performed a contemporary analysis of survival outcomes in patients aged ≥18 years with DLBCL at the population level using linked administrative d…
View article: Effect of single-entry referral models and team-based care on wait times for hip and knee joint replacement in Ontario: a simulation study
Effect of single-entry referral models and team-based care on wait times for hip and knee joint replacement in Ontario: a simulation study Open
Coordinated referral and practice models improve access to scheduled surgery in Canadian health systems. Implementation of these models could largely eliminate prolonged wait times for joint replacement surgery in Ontario.
View article: Evaluating Harms Associated With Prolonged Antibiotic Duration of Therapy in Community-Dwelling Older Adults: A Cohort Study Using Instrumental Variable Analysis
Evaluating Harms Associated With Prolonged Antibiotic Duration of Therapy in Community-Dwelling Older Adults: A Cohort Study Using Instrumental Variable Analysis Open
Background Shorter courses of antibiotic therapy are increasingly recommended to reduce antibiotic exposure. However, quantifying the real-world impact of duration of therapy is hindered by bias common in observational studies. We aimed to…
View article: Referral patterns for common surgical procedures in Ontario: a cross-sectional population-level study
Referral patterns for common surgical procedures in Ontario: a cross-sectional population-level study Open
Improving surgical wait times by coordinating surgical referrals will require approaches that address the structure of existing referral networks. Most physicians refer their patients to a very small number of surgeons, suggesting that ref…
View article: Emergency department use before cancer diagnosis in Ontario, Canada: a population-based study
Emergency department use before cancer diagnosis in Ontario, Canada: a population-based study Open
Emergency department use is common before cancer diagnosis, with about one-third of patients with cancer in Ontario using the emergency department before diagnosis. Understanding why patients visit the emergency department before cancer di…
View article: Surgeon- and hospital-level variation in wait times for scheduled non-urgent surgery in Ontario, Canada: A cross-sectional population-based study
Surgeon- and hospital-level variation in wait times for scheduled non-urgent surgery in Ontario, Canada: A cross-sectional population-based study Open
Background Canadian health systems fare poorly in providing timely access to elective surgical care, which is crucial for quality, trust, and satisfaction. Methods We conducted a cross-sectional analysis of surgical wait times for adults r…
View article: Health care utilization and costs for frail vs nonfrail patients with diffuse large B-cell lymphoma
Health care utilization and costs for frail vs nonfrail patients with diffuse large B-cell lymphoma Open
Half of older patients with diffuse large B-cell lymphoma (DLBCL) receiving curative-intent treatment are frail. Understanding the differences in health care utilization including costs between frail and nonfrail patients can inform approp…
View article: Short‐ and long‐term outcomes of acute diverticulitis in patients with transplanted kidneys
Short‐ and long‐term outcomes of acute diverticulitis in patients with transplanted kidneys Open
Aim The safety of nonoperative treatment for patients with transplanted kidneys who develop acute diverticulitis is unclear. Our primary aim was to examine the long‐term sequelae of nonoperative management in this group. Method We performe…
View article: A multiprovincial retrospective analysis of the incidence of myocarditis or pericarditis after mRNA vaccination compared to the incidence after SARS-CoV-2 infection
A multiprovincial retrospective analysis of the incidence of myocarditis or pericarditis after mRNA vaccination compared to the incidence after SARS-CoV-2 infection Open
View article: Intellectual and developmental disabilities in Ontario's criminal justice and forensic mental health systems: Using data to tell the story
Intellectual and developmental disabilities in Ontario's criminal justice and forensic mental health systems: Using data to tell the story Open
Background International studies show that adults with intellectual and developmental disabilities (IDD) are disproportionately represented in the criminal justice and forensic mental health systems; however, it is difficult to capture the…
View article: Social inequalities in COVID-19 deaths by area-level income: patterns over time and the mediating role of vaccination in a population of 11.2 million people in Ontario, Canada
Social inequalities in COVID-19 deaths by area-level income: patterns over time and the mediating role of vaccination in a population of 11.2 million people in Ontario, Canada Open
Importance Social inequalities in COVID-19 deaths were evident early in the pandemic. Less is known about how vaccination may have influenced inequalities in COVID-19 deaths. Objectives To examine patterns in COVID-19 deaths by area-level …
View article: Social determinants of access to timely elective surgery in Ontario, Canada: a cross-sectional population level study
Social determinants of access to timely elective surgery in Ontario, Canada: a cross-sectional population level study Open
Social disadvantage had a small and inconsistent impact on receiving care within wait time targets. Future research should consider these differences as they relate to resource distribution and the organization of clinical service delivery.
View article: Comparison of socio-economic determinants of COVID-19 testing and positivity in Canada: A multi-provincial analysis
Comparison of socio-economic determinants of COVID-19 testing and positivity in Canada: A multi-provincial analysis Open
Background The effects of the COVID-19 pandemic have been more pronounced for socially disadvantaged populations. We sought to determine how access to SARS-CoV-2 testing and the likelihood of testing positive for COVID-19 were associated w…
View article: Clinical index to quantify the 1-year risk for common postpartum mental disorders at the time of delivery (PMH CAREPLAN): development and internal validation
Clinical index to quantify the 1-year risk for common postpartum mental disorders at the time of delivery (PMH CAREPLAN): development and internal validation Open
Background Common postpartum mental health (PMH) disorders such as depression and anxiety are preventable, but determining individual-level risk is difficult. Aims To create and internally validate a clinical risk index for common PMH diso…
View article: ASSOCIATION OF COVID‐19 PANDEMIC WITH INDOLENT LYMPHOMA CARE DELIVERY AND OUTCOMES IN ONTARIO, CANADA: A POPULATION‐BASED ANALYSIS
ASSOCIATION OF COVID‐19 PANDEMIC WITH INDOLENT LYMPHOMA CARE DELIVERY AND OUTCOMES IN ONTARIO, CANADA: A POPULATION‐BASED ANALYSIS Open
Background: Due to concern for infection risk, the coronavirus disease 2019 (COVID-19) pandemic presented a unique challenge for optimal management of indolent non-Hodgkin lymphoma (iNHL). We examined treatment (trt) selection, healthcare …
View article: Maternal opioid treatment after delivery and risk of adverse infant outcomes: population based cohort study
Maternal opioid treatment after delivery and risk of adverse infant outcomes: population based cohort study Open
Objective To examine whether maternal opioid treatment after delivery is associated with an increased risk of adverse infant outcomes. Design Population based cohort study. Setting Ontario, Canada. Participants 865 691 mother-infant pairs …
View article: Myocarditis or Pericarditis Events After BNT162b2 Vaccination in Individuals Aged 12 to 17 Years in Ontario, Canada
Myocarditis or Pericarditis Events After BNT162b2 Vaccination in Individuals Aged 12 to 17 Years in Ontario, Canada Open
Importance The risk of myocarditis or pericarditis after COVID-19 messenger RNA vaccines varies by age and sex, and there is some evidence to suggest increasing risk with shorter intervals between dose 1 and 2 (ie, interdose interval). Obj…
View article: Association of COVID-19 Vaccination With Breakthrough Infections and Complications in Patients With Cancer
Association of COVID-19 Vaccination With Breakthrough Infections and Complications in Patients With Cancer Open
Importance Patients with cancer are known to have increased risk of COVID-19 complications, including death. Objective To determine the association of COVID-19 vaccination with breakthrough infections and complications in patients with can…
View article: Differential Patterns by Area-Level Social Determinants of Health in Coronavirus Disease 2019 (COVID-19)–Related Mortality and Non–COVID-19 Mortality: A Population-Based Study of 11.8 Million People in Ontario, Canada
Differential Patterns by Area-Level Social Determinants of Health in Coronavirus Disease 2019 (COVID-19)–Related Mortality and Non–COVID-19 Mortality: A Population-Based Study of 11.8 Million People in Ontario, Canada Open
Background Social determinants of health (SDOH) have been associated with coronavirus disease 2019 (COVID-19) outcomes. We examined patterns in COVID-19–related mortality by SDOH and compared these patterns to those for non–COVID-19 mortal…
View article: Association of Influenza Vaccination With SARS-CoV-2 Infection and Associated Hospitalization and Mortality Among Patients Aged 66 Years or Older
Association of Influenza Vaccination With SARS-CoV-2 Infection and Associated Hospitalization and Mortality Among Patients Aged 66 Years or Older Open
Importance Vaccine effectiveness studies have rarely implemented strategies to reduce the healthy vaccinee bias arising from differences in health care–seeking behavior between vaccinated and unvaccinated individuals. Although previous obs…
View article: Epidemiology of Myocarditis and Pericarditis Following mRNA Vaccination by Vaccine Product, Schedule, and Interdose Interval Among Adolescents and Adults in Ontario, Canada
Epidemiology of Myocarditis and Pericarditis Following mRNA Vaccination by Vaccine Product, Schedule, and Interdose Interval Among Adolescents and Adults in Ontario, Canada Open
The findings of this population-based cohort study of Ontario adolescents and adults with myocarditis or pericarditis following mRNA COVID-19 vaccination suggest that vaccine products and interdose intervals, in addition to age and sex, ma…
View article: Predictors of all‐cause mortality among patients hospitalized with influenza, respiratory syncytial virus, or SARS‐CoV‐2
Predictors of all‐cause mortality among patients hospitalized with influenza, respiratory syncytial virus, or SARS‐CoV‐2 Open
Background Shared and divergent predictors of clinical severity across respiratory viruses may support clinical and community responses in the context of a novel respiratory pathogen. Methods We conducted a retrospective cohort study to id…
View article: Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance
Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance Open
View article: Predictors of all-cause mortality among patients hospitalized with influenza, respiratory syncytial virus, or SARS-CoV-2
Predictors of all-cause mortality among patients hospitalized with influenza, respiratory syncytial virus, or SARS-CoV-2 Open
Background Shared and divergent predictors of clinical severity across respiratory viruses may support clinical and community responses in the context of a novel respiratory pathogen. Methods We conducted a retrospective cohort study to id…
View article: Area-level social and structural inequalities determine mortality related to COVID-19 diagnosis in Ontario, Canada: a population-based explanatory modeling study of 11.8 million people
Area-level social and structural inequalities determine mortality related to COVID-19 diagnosis in Ontario, Canada: a population-based explanatory modeling study of 11.8 million people Open
Importance Social determinants of health (SDOH) play an important role in COVID-19 outcomes. More research is needed to quantify this relationship and understand the underlying mechanisms. Objectives To examine differential patterns in COV…
View article: Stringency of containment and closures on the growth of SARS-CoV-2 in Canada prior to accelerated vaccine roll-out
Stringency of containment and closures on the growth of SARS-CoV-2 in Canada prior to accelerated vaccine roll-out Open
View article: Effectiveness of COVID-19 vaccines against symptomatic SARS-CoV-2 infection and severe outcomes with variants of concern in Ontario
Effectiveness of COVID-19 vaccines against symptomatic SARS-CoV-2 infection and severe outcomes with variants of concern in Ontario Open
View article: Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance
Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance Open
Background Background incidence rates are critical in pharmacovigilance to facilitate identification of vaccine safety signals. We estimated background incidence rates of nine adverse events of special interest related to COVID-19 vaccines…