BACKGROUND: Every year in Ontario, the records of over 42 million prescriptions dispensed to persons eligible for Ontario Drug Benefit (ODB) benefits are transmitted to a central database. The ODB database is the second largest database of medications in Canada, containing records on almost half of all medications dispensed in Ontario. There is no information about the reliability of the coding on the ODB drug claims database and, therefore, the objective of this study was to estimate the reliability of coding of the Drug Identification Number, and the date, quantity and duration of the dispensation on claims sent to the ODB. METHODS: To meet this objective, approximately 100 randomly selected prescriptions dispensed from each of 50 pharmacies in southern Ontario between July 1, 1998 and December 31, 1999 were audited. For each claim, the written information on the prescription was compared with the electronic information submitted to the ODB database. Logistic regression was used to test the association between coding errors and the location, owner affiliation, and productivity of each pharmacy (defined as the annual volume of dispensations divided by the annual number of hours worked by all pharmacists and pharmacy assistants). RESULTS: Of the 183 pharmacies owners invited to participate, consent to abstract information was obtained in 50, yielding a participation rate of 27%. Of the 5155 dispensed prescriptions, 37 errors were found, yielding an overall error rate of 0.7% (95% CI 0.5% to 0.9%). None of the characteristics of pharmacies that were examined (location, owner affiliation, productivity) was associated with coding errors. CONCLUSIONS: Pharmacists almost always dispense the medication that is prescribed and this information is reliably transmitted to the ODB drug claims database. This means that any conclusions drawn by researchers using these data are not likely to be compromised by low coding reliability.
BACKGROUND: Cancer Care Ontario's Systemic Therapy Task Force recently reviewed the medical oncology system in the province. There has been growing concern about anecdotal reports of burnout, high levels of stress and staff leaving or decreasing their work hours. However, no research has systematically determined whether there is evidence to support or refute these reports. To this end, a confidential survey was undertaken. METHODS: A questionnaire was mailed to all 1016 personnel of the major providers of medical oncology services in Ontario. The questionnaire consisted of the Maslach Burnout Inventory, the 12-item General Health Questionnaire, a questionnaire to determine job satisfaction and stress, and questions to obtain demographic characteristics and to measure the staff's consideration of alternative work situations. RESULTS: The overall response rate was 70.9% (681 of 961 eligible subjects): by group it was 63.3% (131/207) for physicians, 80.9% (314/388) for allied health professionals and 64.5% (236/366) for support staff. The prevalence of emotional exhaustion were significantly higher among the physicians (53.3%) than among the allied health professionals (37.1%) and the support staff (30.5%) (p < or = 0.003); the same was true for feelings of depersonalization (22.1% v. 4.3% and 5.5% respectively) (p < or = 0.003). Feelings of low personal accomplishment were significantly higher among physicians (48.4%) and allied health professionals (54.0%) than among support staff (31.4%) (p < or = 0.002). About one-third of the respondents in each group reported that they have considered leaving for a job outside the cancer care system. Significantly more physicians (42.6%) than allied health professionals (7.6%) or support staff (4.5%) stated that they have considered leaving for a job outside the province. INTERPRETATION: The findings support the concern that medical oncology personnel are experiencing burnout and high levels of stress and that large numbers are considering leaving or decreasing their work hours. This is an important finding for the cancer care system, where highly trained and experienced health care workers are already in short supply.
OBJECTIVE: To estimate the point prevalence of fibromyalgia syndrome (FM) among noninstitutionalized Canadian adults; and to assess the effect of demographic variables on the odds of having FM. METHODS: A screening questionnaire was administered via telephone to a random community sample of 3395 noninstitutionalized adults residing in London, Ontario. Individuals screening positive were invited to be examined by a rheumatologist to confirm or exclude FM using the 1990 American College of Rheumatology classification criteria. RESULTS: One hundred confirmed cases of FM were identified, of whom 86 were women. Mean age among FM cases was 49.2 years among women, 39.3 years among men (p < 0.02). FM affects an estimated 4.9% (95% CI 4.7%, 5.1%) of adult women and 1.6% (1.3%, 1.9%) of adult men in London, for a female to male ratio of roughly 3 to one. In women, prevalence rises steadily with age from < 1% in women aged 18-30 to almost 8% in women 55-64. Thereafter, it declines. The peak prevalence in men also appears to be in middle age (2.5%; 1.1%, 5.7%). FM affects 3.3% (3.2%, 3.4%) of noninstitutionalized adults in London. Female sex, middle age, less education, lower household income, being divorced, and being disabled are associated with increased odds of having FM. CONCLUSION: FM is a common musculoskeletal disorder among Canadian adults, especially among women and persons of lower socioeconomic status.
Research Article| March 01, 1973 Archean Ultramafic Flows in Munro Township, Ontario D. R. PYKE; D. R. PYKE 1Ontario Division of Mines, Geological Branch, Whitney Block, Queen's Park, Toronto, Ontario, Canada Search for other works by this author on: GSW Google Scholar A. J. NALDRETT; A. J. NALDRETT 2Department of Geology, University of Toronto, Toronto, Ontario, Canada Search for other works by this author on: GSW Google Scholar O. R. ECKSTRAND O. R. ECKSTRAND 3Geological Survey of Canada, 601 Booth Street, Ottawa, Ontario, Canada Search for other works by this author on: GSW Google Scholar GSA Bulletin (1973) 84 (3): 955–978. https://doi.org/10.1130/0016-7606(1973)84<955:AUFIMT>2.0.CO;2 Article history first online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation D. R. PYKE, A. J. NALDRETT, O. R. ECKSTRAND; Archean Ultramafic Flows in Munro Township, Ontario. GSA Bulletin 1973;; 84 (3): 955–978. doi: https://doi.org/10.1130/0016-7606(1973)84<955:AUFIMT>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract A unique exposure within the Abitibi orogenic belt of northeastern Ontario provides an exceptionally clear view of early Precambrian (Archean) ultramafic volcanic rocks. Approximately 60 ultramafic flow units are exposed over a stratigraphic thickness of 125 m. Individual flow units range in thickness from 0.5 to 15 m, average about 3 m, and display remarkable strike lengths and internal structure, which suggest extreme fluidity.The upper margin of the flow units (0.1 to 1.0 m) is thicker than the lower margin (about 1 cm), and the upper margin is highly fractured, thereby providing an easily recognizable top determinator. Many flow units contain a zone of spinifex, ranging in width from zero to 5 m, which underlies and is gradational with the flow top. Spinifex is a textural term to describe an array of criss-crossing sheafs or booklets characterized by numerous closely spaced and parallel blade- or plate-like crystals of olivine. The texture is generally accepted as having formed by rapid cooling of a crystal-free ultramafic liquid in situ. The variation in size of bladed olivine crystals within a spinifex zone is always from coarse (up to 1 m long) at the bottom to fine at the top, thereby providing a primary top determination. In flow units not containing a spinifex zone the chilled and fractured flow top grades downward into a zone of moderately foliated peridotite which generally constitutes the remaining part of a flow unit.Chemically, the flow units resemble similar ultramafic rocks described from northeastern Ontario, western Australia, and the Barberton area of South Africa; one unique feature is the exceptionally high alumina content of the clinopyroxene This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Importance: Medical imaging increased rapidly from 2000 to 2006, but trends in recent years have not been analyzed. Objective: To evaluate recent trends in medical imaging. Design, Setting, and Participants: Retrospective cohort study of patterns of medical imaging between 2000 and 2016 among 16 million to 21 million patients enrolled annually in 7 US integrated and mixed-model insurance health care systems and for individuals receiving care in Ontario, Canada. Exposures: Calendar year and country (United States vs Canada). Main Outcomes and Measures: Use of computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, and nuclear medicine imaging. Annual and relative imaging rates by imaging modality, country, and age (children [<18 years], adults [18-64 years], and older adults [≥65 years]). Results: Overall, 135 774 532 imaging examinations were included; 5 439 874 (4%) in children, 89 635 312 (66%) in adults, and 40 699 346 (30%) in older adults. Among adults and older adults, imaging rates were significantly higher in 2016 vs 2000 for all imaging modalities other than nuclear medicine. For example, among older adults, CT imaging rates were 428 per 1000 person-years in 2016 vs 204 per 1000 in 2000 in US health care systems and 409 per 1000 vs 161 per 1000 in Ontario; for MRI, 139 per 1000 vs 62 per 1000 in the United States and 89 per 1000 vs 13 per 1000 in Ontario; and for ultrasound, 495 per 1000 vs 324 per 1000 in the United States and 580 per 1000 vs 332 per 1000 in Ontario. Annual growth in imaging rates among US adults and older adults slowed over time for CT (from an 11.6% annual percentage increase among adults and 9.5% among older adults in 2000-2006 to 3.7% among adults in 2013-2016 and 5.2% among older adults in 2014-2016) and for MRI (from 11.4% in 2000-2004 in adults and 11.3% in 2000-2005 in older adults to 1.3% in 2007-2016 in adults and 2.2% in 2005-2016 in older adults). Patterns in Ontario were similar. Among children, annual growth for CT stabilized or declined (United States: from 10.1% in 2000-2005 to 0.8% in 2013-2016; Ontario: from 3.3% in 2000-2006 to -5.3% in 2006-2016), but patterns for MRI were similar to adults. Changes in annual growth in ultrasound were smaller among adults and children in the United States and Ontario compared with CT and MRI. Nuclear medicine imaging declined in adults and children after 2006. Conclusions and Relevance: From 2000 to 2016 in 7 US integrated and mixed-model health care systems and in Ontario, rates of CT and MRI use continued to increase among adults, but at a slower pace in more recent years. In children, imaging rates continued to increase except for CT, which stabilized or declined in more recent periods. Whether the observed imaging utilization was appropriate or was associated with improved patient outcomes is unknown.
BACKGROUND: Evidence from observational studies that the use of surgical safety checklists results in striking improvements in surgical outcomes led to the rapid adoption of such checklists worldwide. However, the effect of mandatory adoption of surgical safety checklists is unclear. A policy encouraging the universal adoption of checklists by hospitals in Ontario, Canada, provided a natural experiment to assess the effectiveness of checklists in typical practice settings. METHODS: We surveyed all acute care hospitals in Ontario to determine when surgical safety checklists were adopted. Using administrative health data, we compared operative mortality, rate of surgical complications, length of hospital stay, and rates of hospital readmission and emergency department visits within 30 days after discharge among patients undergoing a variety of surgical procedures before and after adoption of a checklist. RESULTS: During 3-month periods before and after adoption of a surgical safety checklist, a total of 101 hospitals performed 109,341 and 106,370 procedures, respectively. The adjusted risk of death during a hospital stay or within 30 days after surgery was 0.71% (95% confidence interval [CI], 0.66 to 0.76) before implementation of a surgical checklist and 0.65% (95% CI, 0.60 to 0.70) afterward (odds ratio, 0.91; 95% CI, 0.80 to 1.03; P=0.13). The adjusted risk of surgical complications was 3.86% (95% CI, 3.76 to 3.96) before implementation and 3.82% (95% CI, 3.71 to 3.92) afterward (odds ratio, 0.97; 95% CI, 0.90 to 1.03; P=0.29). CONCLUSIONS: Implementation of surgical safety checklists in Ontario, Canada, was not associated with significant reductions in operative mortality or complications. (Funded by the Canadian Institutes of Health Research.).
BACKGROUND: HIV infection rates are increasing among marginalized women in Ontario, Canada. HIV-related stigma, a principal factor contributing to the global HIV epidemic, interacts with structural inequities such as racism, sexism, and homophobia. The study objective was to explore experiences of stigma and coping strategies among HIV-positive women in Ontario, Canada. METHODS AND FINDINGS: We conducted a community-based qualitative investigation using focus groups to understand experiences of stigma and discrimination and coping methods among HIV-positive women from marginalized communities. We conducted 15 focus groups with HIV-positive women in five cities across Ontario, Canada. Data were analyzed using thematic analysis to enhance understanding of the lived experiences of diverse HIV-positive women. Focus group participants (n = 104; mean age = 38 years; 69% ethnic minority; 23% lesbian/bisexual; 22% transgender) described stigma/discrimination and coping across micro (intra/interpersonal), meso (social/community), and macro (organizational/political) realms. Participants across focus groups attributed experiences of stigma and discrimination to: HIV-related stigma, sexism and gender discrimination, racism, homophobia and transphobia, and involvement in sex work. Coping strategies included resilience (micro), social networks and support groups (meso), and challenging stigma (macro). CONCLUSIONS: HIV-positive women described interdependent and mutually constitutive relationships between marginalized social identities and inequities such as HIV-related stigma, sexism, racism, and homo/transphobia. These overlapping, multilevel forms of stigma and discrimination are representative of an intersectional model of stigma and discrimination. The present findings also suggest that micro, meso, and macro level factors simultaneously present barriers to health and well being--as well as opportunities for coping--in HIV-positive women's lives. Understanding the deleterious effects of stigma and discrimination on HIV risk, mental health, and access to care among HIV-positive women can inform health care provision, stigma reduction interventions, and public health policy.
UNLABELLED: Cardiac sarcoidosis is a potentially fatal complication of sarcoidosis. The 1993 guidelines of the Ministry of Health, Labour, and Welfare (MHLW) of Japan have been used as the diagnostic gold standard and for comparison with imaging modalities. (18)F-FDG PET is not currently included in the guidelines. However, studies have shown promising data using (18)F-FDG PET. We conducted a systematic review of studies that evaluated the accuracy of (18)F-FDG PET for the diagnosis of cardiac sarcoidosis compared with MHLW guidelines. Data from a prospective Ontario provincial registry are also reported and included in the metaanalysis. METHODS: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched for studies that satisfied predetermined criteria. Quality evaluation using the Quality Assessment for Diagnostic Accuracy Studies was performed by 2 independent masked observers. Data were extracted and analyzed to measure study-specific and pooled accuracy for (18)F-FDG PET compared with the MHLW as the reference. RESULTS: A total of 519 titles was identified; 7 studies, including the Ontario registry, were selected for inclusion. Metaanalysis of these 7 studies was conducted, with a total of 164 patients, most of whom had been diagnosed with systemic sarcoidosis. The prevalence of cardiac sarcoidosis was 50% in the whole population. Pooled estimates for (18)F-FDG PET yielded 89% sensitivity (95% confidence interval [CI], 79%-96%), 78% specificity (95% CI, 68%-86%), a 4.1 positive likelihood ratio (95% CI, 1.7-10), and a 0.19 negative likelihood ratio (95% CI, 0.1-0.4). The overall diagnostic odds ratio was 25.6 (95% CI, 7.3-89.5), and the area under the summary receiver operator characteristic curve was 93% ± 3.5. The Ontario study yielded sensitivity and specificity of 79% and 70%, respectively. CONCLUSION: The high diagnostic accuracy determined for (18)F-FDG PET in this metaanalysis suggests potential value for diagnosis of cardiac sarcoidosis compared with the MHLW guidelines. These results may affect patient care by providing supportive evidence for more effective use of (18)F-FDG PET in the diagnosis of cardiac sarcoidosis. Large-scale multicenter studies are required to further evaluate this role.
BACKGROUND: Physical-distancing interventions are being used in Canada to slow the spread of severe acute respiratory syndrome coronavirus 2, but it is not clear how effective they will be. We evaluated how different nonpharmaceutical interventions could be used to control the coronavirus disease 2019 (COVID-19) pandemic and reduce the burden on the health care system. METHODS: We used an age-structured compartmental model of COVID-19 transmission in the population of Ontario, Canada. We compared a base case with limited testing, isolation and quarantine to scenarios with the following: enhanced case finding, restrictive physical-distancing measures, or a combination of enhanced case finding and less restrictive physical distancing. Interventions were either implemented for fixed durations or dynamically cycled on and off, based on projected occupancy of intensive care unit (ICU) beds. We present medians and credible intervals from 100 replicates per scenario using a 2-year time horizon. RESULTS: We estimated that 56% (95% credible interval 42%-63%) of the Ontario population would be infected over the course of the epidemic in the base case. At the epidemic peak, we projected 107 000 (95% credible interval 60 760-149 000) cases in hospital (non-ICU) and 55 500 (95% credible interval 32 700-75 200) cases in ICU. For fixed-duration scenarios, all interventions were projected to delay and reduce the height of the epidemic peak relative to the base case, with restrictive physical distancing estimated to have the greatest effect. Longer duration interventions were more effective. Dynamic interventions were projected to reduce the proportion of the population infected at the end of the 2-year period and could reduce the median number of cases in ICU below current estimates of Ontario's ICU capacity. INTERPRETATION: Without substantial physical distancing or a combination of moderate physical distancing with enhanced case finding, we project that ICU resources would be overwhelmed. Dynamic physical distancing could maintain health-system capacity and also allow periodic psychological and economic respite for populations.
OBJECTIVE: Although rates of mental health service utilization differ dramatically across countries, little information is available about differences in self-reported barriers to mental health service utilization. Perceived barriers were examined in three locations with differing health care systems. METHODS: Data came from three methodologically similar population-based surveys of adults conducted in the 1990s in Ontario, Canada (N=6,261), the United States (N=5,384), and the Netherlands (N=6,031) that assessed DSM-III-R nonpsychotic mental disorders with the Composite International Diagnostic Interview. Respondents who reported a need for professional help were asked to indicate reasons for not seeking care. Multiple logistic regression analyses were used to determine the sociodemographic, mental disorder, and location-specific correlates of each perceived barrier. RESULTS: The pattern of reported barriers to mental health service utilization was similar across locations: attitudinal barriers (thoughts that the problem would get better on its own) were more prevalent than structural barriers (inability to get an appointment). Fear of stigmatization was not commonly endorsed. With adjustment for sociodemographic factors and type of mental disorder, low-income respondents were significantly more likely to report a financial barrier in the United States than in either Ontario or the Netherlands. CONCLUSIONS: Across locations, attitudinal barriers were more likely to be endorsed than structural barriers to service utilization. The most striking reported cross-national difference was structural, with many more U.S. respondents (especially those with low incomes) reporting financial barriers than respondents in either Ontario or the Netherlands.
PURPOSE: To describe trends in the aggressiveness of end-of-life (EOL) cancer care in a universal health care system in Ontario, Canada, between 1993 and 2004, and to compare with findings reported in the United States. METHODS: A population-based, retrospective, cohort study that used administrative data linked to registry data. Aggressiveness of EOL care was defined as the occurrence of at least one of the following indicators: last dose of chemotherapy received within 14 days of death; more than one emergency department (ED) visit within 30 days of death; more than one hospitalization within 30 days of death; or at least one intensive care unit (ICU) admission within 30 days of death. RESULTS: Among 227,161 patients, 22.4% experienced at least one incident of potentially aggressive EOL cancer care. Multivariable analyses showed that with each successive year, patients were significantly more likely to encounter some aggressive intervention (odds ratio, 1.01; 95% CI, 1.01 to 1.02). Multiple emergency department (ED) visits, ICU admissions, and chemotherapy use increased significantly over time, whereas multiple hospital admissions declined (P < .05). Patients were more likely to receive aggressive EOL care if they were men, were younger, lived in rural regions, had a higher level of comorbidity, or had breast, lung, or hematologic malignancies. Chemotherapy and ICU utilization were lower in Ontario than in the United States. CONCLUSION: Aggressiveness of cancer care near the EOL is increasing over time in Ontario, Canada, although overall rates were lower than in the United States. Health system characteristics and patient or physician cultural factors may play a role in the observed differences.
BACKGROUND: Globally, primary care changed dramatically as a result of the coronavirus disease 2019 (COVID-19) pandemic. We aimed to understand the degree to which office and virtual primary care changed, and for which patients and physicians, during the initial months of the pandemic in Ontario, Canada. METHODS: This population-based study compared comprehensive, linked primary care physician billing data from Jan. 1 to July 28, 2020, with the same period in 2019. We identified Ontario residents with at least 1 office or virtual (telephone or video) visit during the study period. We compared trends in total physician visits, office visits and virtual visits before COVID-19 with trends after pandemic-related public health measures changed the delivery of care, according to various patient and physician characteristics. We used interrupted time series analysis to compare trends in the early and later halves of the COVID-19 period. RESULTS: Compared with 2019, total primary care visits between March and July 2020 decreased by 28.0%, from 7.66 to 5.51 per 1000 people/day. The smallest declines were among patients with the highest expected health care use (8.3%), those who could not be attributed to a primary care physician (10.2%), and older adults (19.1%). In contrast, total visits in rural areas increased by 6.4%. Office visits declined by 79.1% and virtual care increased 56-fold, comprising 71.1% of primary care physician visits. The lowest uptake of virtual care was among children (57.6%), rural residents (60.6%) and physicians with panels of ≥ 2500 patients (66.0%). INTERPRETATION: Primary care in Ontario saw large shifts from office to virtual care over the first 4 months of the COVID-19 pandemic. Total visits declined least among those with higher health care needs. The determinants and consequences of these major shifts in care require further study.
BACKGROUND: The prevalence of pulmonary non-tuberculous mycobacteria (NTM) infection is reportedly increasing. A study was undertaken of the "isolation prevalence" of pulmonary NTM in Ontario, Canada between 1997 and 2003 and the frequency of pulmonary NTM "disease". METHODS: In a retrospective cohort, the "isolation prevalence" was studied by reviewing all positive NTM culture results from the Tuberculosis and Mycobacteriology Laboratory, Ministry of Health and Long-Term Care in Toronto from 1997 to 2003. This laboratory identifies at least 90% of NTM isolates in Ontario, Canada. Prevalence was compared between years using a negative binomial model. To study the frequency of "disease" (defined by American Thoracic Society criteria), the records of patients who had an isolate in 2003 and had been assessed at our hospital were reviewed. RESULTS: 22,247 pulmonary isolates were obtained from 10,231 patients. The "isolation prevalence" of all species (excluding Mycobacterium gordonae) was 9.1/100,000 in 1997, rising to 14.1/100,000 by 2003 (p<0.0001) with a mean annual increase of 8.4%. Similar increases were observed for individual species. 200 patients assessed at our institution were studied using American Thoracic Society criteria for "disease". Microbiological criteria were fulfilled by 37%. Of patients with adequate data, 74% fulfilled clinical criteria, 77% fulfilled radiological criteria and 33% fulfilled all criteria. CONCLUSIONS: The "isolation prevalence" of pulmonary NTM has significantly and rapidly increased in Ontario; a sizeable proportion of patients are likely to have "disease".
BACKGROUND: Available information on the prevalence and management of hypertension in the Canadian population dates back to 1986-1992 and probably does not reflect the current status of this major risk factor for cardiovascular disease. We sought to evaluate the current prevalence and management of hypertension among adults in the province of Ontario. METHODS: Potential respondents from randomly selected dwellings within target neighbourhoods in 16 municipalities were contacted at their homes to request participation in the study. For potential respondents who agreed to participate, blood pressure was measured with an automated device. Estimation weights were used to obtain representative estimates of population parameters. Responses were weighted to the total adult population in Ontario of 7,996,653. RESULTS: From 6436 eligible dwellings, contact was made with 4559 potential participants, of whom 2992 agreed to participate. Blood pressure measurements were obtained for 2551 of these respondents (age 20-79 years). Hypertension, defined as systolic blood pressure of 140 mm Hg or more, diastolic blood pressure of 90 mm Hg or more, or treatment with an antihypertensive medication, was identified in 21.3% of the population overall (23.8% of men and 19.0% of women). Prevalence increased with age, from 3.4% among participants 20-39 years of age to 51.6% among those 60-79 years of age. Hypertension was more common among black people and people of South Asian background than among white people; hypertension was also associated with higher body mass index. Among participants with hypertension, 65.7% were undergoing treatment with control of hypertension, 14.7% were undergoing treatment but the hypertension was not controlled, and 19.5% were not receiving any treatment (including 13.7% who were unaware of their hypertension). The extent of control of hypertension did not differ significantly by age, sex, ethnic background or comorbidities. INTERPRETATION: In Ontario, the overall prevalence of hypertension is high in the older population but appears not to have increased in recent decades. Hypertension management has improved markedly among all age groups and for both sexes.
OBJECTIVE: Accurate information about the magnitude and distribution of diabetes can inform policy and support health care evaluation. We linked physician service claims (PSCs) and hospital discharge abstracts (HDAs) to determine diabetes prevalence and incidence. RESEARCH DESIGN AND METHODS: A retrospective cohort was constructed using administrative data from the national HDA database, PSCs for Ontario (population 11 million), and registries carrying demographics and vital statistics. All HDAs and PSCs bearing a diagnosis of diabetes (ICD9-CM 250) were selected for 1991-1999. Two previously reported algorithms for identification of diabetes were applied as follows: "1-claim" (any HDA or PSC showing diabetes) and "2-claim" (one HDA or two PSCs within 2 years showing diabetes). Incident cases were defined as individuals who met the criteria for diabetes for the first time after at least 2 years of observation. For validation, diagnostic data abstracted from primary care charts (n=3,317) of 57 randomly selected physicians were linked to the administrative data cohort, and sensitivity and specificity were calculated. RESULTS: -In 1998, 696,938 individuals met the 1-claim criteria and 528,280 met the 2-claim criteria. Sensitivity for diabetes was 90 and 86%; for the 1- and 2-claim algorithms, specificity was 92 and 97%, respectively, and positive predictive values were 61 and 80%, respectively. Using the 2-claim algorithm, the all-age prevalence increased from 3.2% in 1993 to 4.5% in 1998 (6.1% in adults). Incidence remained stable. CONCLUSIONS: Administrative data can be used to establish population-based incidence and prevalence of diabetes. Diabetes prevalence is increasing in Ontario and is considerably higher than self-reported rates.
Perfluorooctane sulfonate (PFOS) is a persistent and bioaccumulative perfluorinated acid detectable in humans and wildlife worldwide that has alerted scientists to examine the environmental fate of other fluorinated organic contaminants. Recently a homologous series of perfluoroalkyl carboxylates (PFCAs) was detected in the Arctic, yet little is known about their sources, breadth of contamination, or environmental distribution. In this study we analyzed for PFOS, the homologous series of PFCAs ranging from 8 to 15 carbons in chain length, and the PFOS-precursor heptadecafluorooctane sulfonamide (FOSA) in various organisms from a food web of Lake Ontario. The sampled organisms included a top predator fish, lake trout (Salvelinus namaycush), three forage fish species including rainbow smelt (Osmerus mordax), slimy sculpin (Cottus cognatus), and alewife (Alosa pseudoharengus), and two invertebrates Diporeia (Diporeia hoyi) and Mysis (Mysis relicta). A striking finding was that the highest mean concentration for each fluorinated contaminantwas detected in the benthic macroinvertebrate Diporeia, which occupies the lowest trophic level of all organisms analyzed. Perfluorinated acid concentrations in Diporeia were often 10-fold higher than in Mysis, a predominantly pelagic feeder, suggesting that a major source of perfluoroalkyl contaminants to this food web was the sediment, not the water. PFOS was the dominant acid in all samples, but long-chain PFCAs, ranging in length from 8 to 15 carbons, were also detected in most samples between <0.5 and 90 ng/ g. Among Mysis and the more pelagic fish species (e.g. excluding Diporeia and sculpin) there was evidence for biomagnification, but the influence of foraging on highly contaminated Diporeia and sculpin by these fish may have overestimated trophic magnification factors (TMFs), which ranged from 0.51 for FOSA to 5.88 for PFOS. By accounting for the known diet composition of lake trout, it was shown that bioaccumulation was indeed occurring at the top of the food web for all perfluoroalkyl compounds except PFOA. Future monitoring at other locations in Lake Ontario, and in other aquatic environments, is necessary to determine if these food web dynamics are widespread. Archived lake trout samples collected between 1980 and 2001 showed that mean whole body PFOS concentrations increased from 43 to 180 ng/g over this period, but not linearly, and may have been indirectly influenced by the invasion and proliferation of zebra mussels (Dreissena polymorpha) through effects on the population and ecology of forage fishes.
PURPOSE: To determine the prevalence of use of complementary/alternative medicine (CAM) by breast cancer survivors in Ontario, Canada, and to compare the characteristics of CAM users and CAM nonusers. PATIENTS AND METHODS: A questionnaire was mailed to a random sample of Ontario women diagnosed with breast cancer in 1994 or 1995. RESULTS: The response rate was 76.3%. Overall, 66.7% of the respondents reported using CAM, most often in an attempt to boost the immune system. CAM practitioners (most commonly chiropractors, herbalists, acupuncturists, traditional Chinese medicine practitioners, and/or naturopathic practitioners) were visited by 39.4% of the respondents. In addition, 62.0% reported use of CAM products (most frequently vitamins/minerals, herbal medicines, green tea, special foods, and essiac). Almost one half of the respondents informed their physicians of their use of CAM. Multiple logistic regression analysis determined that support group attendance was the only factor significantly associated with CAM use. CONCLUSION: CAM use is common among Canadian breast cancer survivors, many of whom are discussing CAM therapy options with their physicians. Knowledge of CAM therapies is necessary for physicians and other health care practitioners to help patients make informed choices. CAM use may play a role in the positive benefits associated with support group attendance.
Annual decreases in soybean (Glycine max L. Merrill) yield caused by diseases were estimated by surveying university-affiliated plant pathologists in 28 soybean-producing states in the United States and in Ontario, Canada, from 2010 through 2014. Estimated yield losses from each disease varied greatly by state or province and year. Over the duration of this survey, soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) was estimated to have caused more than twice as much yield loss than any other disease. Seedling diseases (caused by various pathogens), charcoal rot (caused by Macrophomina phaseolina (Tassi) Goid), and sudden death syndrome (SDS) (caused by Fusarium virguliforme O’Donnell & T. Aoki) caused the next greatest estimated yield losses, in descending order. The estimated mean economic loss due to all soybean diseases, averaged across U.S. states and Ontario from 2010 to 2014, was $60.66 USD per acre. Results from this survey will provide scientists, breeders, governments, and educators with soybean yield-loss estimates to help inform and prioritize research, policy, and educational efforts in soybean pathology and disease management.
BACKGROUND: A growing body of research suggests that the suburbanization of food retailers in North America and the United Kingdom in recent decades has contributed to the emergence of urban 'food deserts', or disadvantaged areas of cities with relatively poor access to healthy and affordable food. This paper explores the evolution of food deserts in a mid-sized Canadian city (London, Ontario) by using a geographic information system (GIS) to map the precise locations of supermarkets in 1961 and 2005; multiple techniques of network analysis were used to assess changing levels of supermarket access in relation to neighbourhood location, socioeconomic characteristics, and access to public transit. RESULTS: The findings indicate that residents of inner-city neighbourhoods of low socioeconomic status have the poorest access to supermarkets. Furthermore, spatial inequalities in access to supermarkets have increased over time, particularly in the inner-city neighbourhoods of Central and East London, where distinct urban food deserts now exist. CONCLUSION: Contrary to recent findings in larger Canadian cities, we conclude that urban food deserts exist in London, Ontario. Policies aimed at improving public health must also recognize the spatial, as well as socioeconomic, inequities with respect to access to healthy and affordable food. Additional research is necessary to better understand how supermarket access influences dietary behaviours and related health outcomes.
We examined the relationship between the richness of four different wetland taxa (birds, mammals, herptiles, and plants) in 30 southeastern Ontario, Canada wetlands and two anthropogenic factors: road construction and forest removal/conversion on adjacent lands. Data were obtained from two sources: road densities and forest cover from 1:50,000 Government of Canada topographic maps and species lists and wetland areas from Ontario Ministry of Natural Resources wetland evaluation reports. Multiple regression analysis was used to model the relationships between species richness and wetland area, road density, and forest cover. Our results show a strong positive relationship between wetland area and species richness for all taxa. The species richness of all taxa except mammals was negatively correlated with the density of paved roads on lands up to 2 km from the wetland. Furthermore, both herptile and mammal species richness showed a strong positive correlation with the proportion of forest cover on lands within 2 km. These results provide evidence that at the landscape level, road construction and forest removal on adjacent lands pose significant risks to wetland biodiversity. Furthermore, they suggest that most existing wetland policies, which focus almost exclusively on activities within the wetland itself and/or a narrow buffer zone around the wetland perimeter, are unlikely to provide adequate protection for wetland biodiversity.