Comparison of cardiovascular risk profiles among ethnic groups using population health surveys between 1996 and 2007.

Background: Although people of South Asian, Chinese and black ethnic backgrounds represent about 60% of the world's population, most knowledge of cardiovascular risk is derived from studies conducted in white populations. We conducted a large, population-based comparison of cardiovascular risk among people of white, South Asian, Chinese and black ethnicity living in Ontario, Canada.

Methods: We examined the age- and sex-standardized prevalence of eight cardiovascular risk factors, heart disease and stroke among 154,653 white people, 3364 South Asian people, 3038 Chinese people and 2742 black people.

Income-related differences in mortality among people with diabetes mellitus.

Background: Mortality has declined substantially among people with diabetes mellitus over the last decade. Whether all income groups have benefited equally, however, is unclear. We examined the impact of income on mortality trends among people with diabetes.

Revisiting the possibility of serious adverse events from the whole cell pertussis vaccine: were metabolically vulnerable children at risk?

In the early 1980's concerns about the safety of the whole cell pertussis vaccine in the United States resulted in declining vaccination rates and the withdrawal of multiple vaccine providers from the market. While the possibility of inflammation and febrile reactions to the vaccine were acknowledged by public health authorities, parents also claimed the vaccine was associated with sudden infant death syndrome and encephalopathy. Epidemiological studies examining this question, however, consistently failed to identify an association.

Trends in risk factors for cardiovascular disease in Canada: temporal, socio-demographic and geographic factors.

Background: Temporal trends in risk factors for cardiovascular disease and the impact of socio-economic status on these risk factors remain unclear.

Methods: Using data from the National Population Health Survey and the Canadian Community Health Survey, we examined national trends in heart disease, hypertension, diabetes mellitus, obesity and smoking prevalence from 1994 to 2005, adjusting for age and sex. We stratified data by income adequacy category, body mass index and region of residence.

Inter-facility patient transfers in ontario: do you know what your local ambulance is being used for?

Background: Little is known about inter-facility patient transfers in populations. In 2003, detailed information about inter-facility patient transfers began to be systematically collected in Ontario.

Methodology: The authors undertook a descriptive examination of inter-facility patient transfers using a newly created population-based information system.

Trends in laboratory testing for diabetes in Ontario, Canada 1995-2005: a population-based study.

Background: There are concerns that testing for type 2 diabetes is low and many people with diabetes are not diagnosed. We sought to describe the rates of diabetes-related lab testing in Ontario from 1995-2005, among adults without diabetes, and to explore the extent to which the Canadian clinical practice guidelines for screening are being followed.

Methods: Descriptive counts of outpatient diabetes laboratory tests performed within Ontario's publicly funded, provincial health insurance program were recorded.

The effect of universal influenza immunization on mortality and health care use.

Background: In 2000, Ontario, Canada, initiated a universal influenza immunization program (UIIP) to provide free influenza vaccines for the entire population aged 6 mo or older. Influenza immunization increased more rapidly in younger age groups in Ontario compared to other Canadian provinces, which all maintained targeted immunization programs. We evaluated the effect of Ontario's UIIP on influenza-associated mortality, hospitalizations, emergency department (ED) use, and visits to doctors' offices.

Health impact of hospital restrictions on seriously ill hospitalized patients: lessons from the Toronto SARS outbreak.

Background: Restrictions on non-urgent hospital care imposed to control the 2003 Toronto severe acute respiratory syndrome outbreak led to substantial disruptions in hospital clinical practice, admission, and transfer patterns.

Objectives: We assessed whether there were unintended health consequences to seriously ill hospitalized patients. STUDY DESIGN, SETTING, AND POPULATION: Population-based longitudinal cohort study of patients residing in Toronto or an urban control region with an incident admission for 1 of 7 serious conditions in the 3 years before, or the 4 months during or after restrictions.

The 2006 Canadian dyslipidemia guidelines will prevent more deaths while treating fewer people--but should they be further modified?

Background: When clinical guidelines affect large numbers of individuals or substantial resources, it is important to understand their benefits, harms and costs from a population perspective. Many countries' dyslipidemia guidelines include these perspectives.

Objective: To compare the effectiveness and efficiency of the 2003 and 2006 Canadian dyslipidemia guidelines for statin treatment in reducing deaths from coronary artery disease (CAD) in the Canadian population.

Self-reported diabetes is associated with self-management behaviour: a cohort study.

Background: The purposes of this cohort study were to establish how frequently people with physician-diagnosed diabetes self-reported the disease, to determine factors associated with self-reporting of diabetes, and to evaluate subsequent differences in self-management behaviour, health care utilisation and clinical outcomes between people who do and do not report their disease.

Methods: We used a registry of physician-diagnosed diabetes as a reference standard. We studied respondents to a 2000/01 population-based health survey who were in the registry (n = 1,812), and we determined the proportion who reported having diabetes during the survey.

Immunization coverage among young children of urban immigrant mothers: findings from a universal health care system.

Objective: To investigate access to effective primary health care services in children of new immigrants to Canada by assessing immunization coverage at age 2.

Methods: We used multiple linked administrative data sets to analyze primary health service use and immunizations of children born between July 1, 1997, and June 30, 1998, in Ontario, Canada. These children were linked via their mothers' records to a federal Landed Immigrant Database.

An outbreak of cyclosporiasis in 1996 associated with consumption of fresh berries- Ontario.

Background: A large foodborne outbreak of cyclosporiasis occurred in North America in 1996. An index cluster of cases associated with a catered event on May 11, 1996, in Ontario sparked the recognition of this outbreak in Canada.

Objectives: To describe the Ontario experience with the North American outbreak of cyclosporiasis in 1996.

Adopting health behavior change theory throughout the clinical practice guideline process.

Adopting a theoretical framework throughout the clinical practice guideline (CPG) process (development, dissemination, implementation, and evaluation) can be useful in systematically identifying, addressing, and explaining behavioral influences impacting CPG uptake and effectiveness. This article argues that using a theoretical framework should increase the utility and probably the implementation of a CPG. A hypothetical scenario is provided using the theory of planned behavior (TPB) to aid in our explanation.

Quantifying the impact of obesity category on major chronic diseases in Canada.

Adverse health effects differ with various levels of obesity, but limited national data existed previously for the Canadian population. We examined the associations of sociodemographic and behavioral factors with obesity levels in Canada, and measured the impact of each level on major chronic diseases. Data were extracted from the 2003 Canadian Community Health Survey.

How many people have had a myocardial infarction? Prevalence estimated using historical hospital data.

Background: Health administrative data are increasingly used to examine disease occurrence. However, health administrative data are typically available for a limited number of years - posing challenges for estimating disease prevalence and incidence. The objective of this study is to estimate the prevalence of people previously hospitalized with an acute myocardial infarction (AMI) using 17 years of hospital data and to create a registry of people with myocardial infarction.

Effect of widespread restrictions on the use of hospital services during an outbreak of severe acute respiratory syndrome.

Background: Restrictions on the nonurgent use of hospital services were imposed in March 2003 to control an outbreak of severe acute respiratory syndrome (SARS) in Toronto, Ont. We describe the impact of these restrictions on health care utilization and suggest lessons for future epidemics.

Methods: We performed a retrospective population-based study of the Greater Toronto Area (hereafter referred to as Toronto) and unaffected comparison regions (Ottawa and London, Ont.

Decreasing prevalence combined with increasing eradication of Helicobacter pylori infection in the United States has not resulted in fewer hospital admissions for peptic ulcer disease-related complications.

Background: Helicobacter pylori infection is a major cause of peptic ulcer disease, but the prevalence of this infection has been decreasing steadily. Additionally, eradication of H. pylori decreases ulcer recurrence and prevents ulcer complications such as bleeding.

Lessons learned in systems change initiatives: benchmarks and indicators.

Measuring progress toward systems change, sustainable efforts that address root causes of an issue by changing policies and practices, is a difficult task for communities, evaluators, and foundations. Tracking and documenting changes in resources, power, policy, sustainable funding, structured relationships and roles, and underlying values require multi-level analyses. Systems change analysts must consider at least four "strata" at once: (1) events and trends, (2) patterns of interaction, (3) context and cultural or social models, and (4) the systems themselves.

Avoidable mortality by neighbourhood income in Canada: 25 years after the establishment of universal health insurance.

Aim: To examine neighbourhood income differences in deaths amenable to medical care and public health over a 25-year period after the establishment of universal insurance for doctors and hospital services in Canada.

Methods: Data for census metropolitan areas were obtained from the Canadian Mortality Database and population censuses for the years 1971, 1986, 1991 and 1996. Deaths amenable to medical care, amenable to public health, from ischaemic heart disease and from other causes were considered.

Guillain-Barré syndrome after influenza vaccination in adults: a population-based study.

Background: Whether influenza vaccination is associated with Guillain-Barré syndrome (GBS) remains uncertain.

Methods: We conducted 2 studies using population-based health care data from the province of Ontario, Canada. In the first study, we used the self-matched case-series method to explore the temporal association between probable influenza vaccination (adults vaccinated during October and November) and subsequent hospitalization because of GBS.