Canadian National Research Articles

Mortality and Life Expectancy Lost in Canada Attributable to Dietary Patterns: Evidence From Canadian National Nutrition Survey Linked to Routinely Collected Health Administrative Databases.

Using 5 diet quality indexes, we estimated the mortality and life expectancy lost, at the national level, attributable to poor dietary patterns, which had previously been largely unknown. We used the Canadian Community Health Survey 2004, linked to vital statistics (n= 16,212 adults; representing n= 22,898,880). After a median follow-up of 7.5 years, 1,722 deaths were recorded. Population attributable fractions were calculated to estimate the mortality burden of poor dietary patterns (Dietary Guidelines for Americans Adherence Index 2015, Dietary Approaches to Stop Hypertension, Healthy Eating Index, Alternative Healthy Eating Index, and Mediterranean Style Dietary Pattern Score). Better diet quality was associated with a 32%-51% and 21%-43% reduction in all-cause mortality among adults aged 45-80 years and≥20 years, respectively. Projected life expectancy at 45 years was longer for Canadians adhering to a healthy dietary pattern (average of 5.2-8.0 years (men) and 1.6-4.1 (women)). At the population level, 26.5%-38.9% (men) and 8.9%-22.9% (women) of deaths were attributable to poor dietary patterns. Survival benefit was greater for individuals with higher scores on all diet indexes, even with relatively small intake differences. The large attributable burden was likely from assessing overall dietary patterns instead of a limited range of foods and nutrients.

Port-based seafarers’ welfare in Canada: resources and gaps

The ultimate intention of seafarer welfare services is for maritime workers to be served in Canada as systematically and effectively as possible while considering the greatest possible sensitivity to their needs. This paper provides an overview of such services available in Canadian ports and includes case studies of the Port of St. John’s, Newfoundland and Labrador (NL), and of the Catholic seafarers’ ministry, Stella Maris. Two research questions were addressed: 1) where and how is the welfare of foreign seafarers in Canadian ports inadequate, and 2) how can the expertise and resources of those already involved be marshalled to improve support? Existing research on seafarers’ welfare was synthesized, seafarers’ welfare professionals across Canada consulted through interviews and surveys, and key informants were interviewed in the Port of St. John’s, NL. The research findings show that Canadian charities, businesses, government, and labour representatives are united in support of seafarers’ welfare. Furthermore, there is a general interest in filling gaps where they are found, particularly through participation in the Canadian National Seafarers’ Welfare Board. Welfare organizations also actively promote cooperation, professionalism, and the development of new resources for seafarers’ welfare. However, there are still gaps: foreign seafarers are offered a wide range of services in many Canadian ports but internet and enforcement of the Maritime Labour Convention, 2006′s standards for shore leave and crew change are still pressing welfare issues. Welfare workers are stretched thin everywhere and some busy ports must make do with the best efforts of shipping agents where welfare workers are absent. In response to these limitations to seafarer welfare supports, we recommend that the Canadian government, as agents active within a maritime nation, and the maritime community take a more active role in supporting seafarers’ welfare, including financially and through welfare boards.

Perceptions and Practices for Thyroid Surgical Reporting: A Canadian National Study

Perceptions and Practices for Thyroid Surgical Reporting: A Canadian National Study

A Canadian National Survey of the Neurosurgical Management of Intracranial Abscesses.

Intracerebral abscess is a life-threatening condition for which there are no current, widely accepted neurosurgical management guidelines. The purpose of this study was to investigate Canadian practice patterns for the medical and surgical management of primary, recurrent, and multiple intracerebral abscesses. A self-administered, cross-sectional, electronic survey was distributed to active staff and resident members of the Canadian Neurosurgical Society and Canadian Neurosurgery Research Collaborative. Responses between subgroups were analyzed using the Chi-square test. In total, 101 respondents (57.7%) completed the survey. The majority (60.0%) were staff neurosurgeons working in an academic, adult care setting (80%). We identified a consensus that abscesses >2.5 cm in diameter should be considered for surgical intervention. The majority of respondents were in favor of excising an intracerebral abscess over performing aspiration if located superficially in non-eloquent cortex (60.4%), located in the posterior fossa (65.4%), or causing mass effect leading to herniation (75.3%). The majority of respondents were in favor of reoperation for recurrent abscesses if measuring greater than 2.5 cm, associated with progressive neurological deterioration, the index operation was an aspiration and did not include resection of the abscess capsule, and if the recurrence occurred despite prior surgery combined with maximal antibiotic therapy. There was no consensus on the use of topical intraoperative antibiotics. This survey demonstrated heterogeneity in the medical and surgical management of primary, recurrent, and multiple brain abscesses among Canadian neurosurgery attending staff and residents.

Trends and characteristics of Tdap vaccination during pregnancy in Ontario, Canada: a retrospective cohort study.

In February 2018, Canada's National Advisory Committee on Immunization (NACI) recommended tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccination during pregnancy to protect newborns against pertussis infection. We sought to describe pre- and postrecommendation trends in Tdap vaccination coverage among pregnant Ontario residents. Using linked health administrative databases, we conducted a population-based retrospective cohort study of all pregnant individuals who gave birth in Ontario hospitals between April 2012 and March 2020. We described Tdap vaccination patterns in pregnancy for the entire study period and before and after the NACI recommendation. We used log-binomial regression to identify characteristics associated with Tdap vaccination during pregnancy. Among the 991 850 deliveries included, 7.0% of pregnant individuals received the Tdap vaccination during pregnancy. Vaccine coverage increased from 0.4% in 2011/12 to 29.2% in 2019/20. Coverage was highest among individuals who were older, had no previous live births, had adequate prenatal care and received maternity care primarily from a family physician. After adjustment, characteristics associated with lower coverage included younger maternal age, having a multiple birth, residing in a rural location and higher area material deprivation. In 2019/20, 71.0% of vaccinated individuals received the Tdap vaccination during the recommended gestational window (27-32 wk). Stratified analyses of the pre- and postrecommendation cohorts yielded similar findings to the main analyses with a few gradient differences after adjustment. During pregnancy, Tdap vaccination coverage increased substantially in Ontario between 2011/12 and 2019/20, most notably after recommendations for universal Tdap vaccination during pregnancy began in Canada. To further improve vaccine coverage in the obstetric setting, public health strategies should consider tailoring their programs to reach subpopulations with lower vaccine coverage.

Fiber Bragg Grating Sensors ice detection: Methodologies and performance

New Researches have been done recently in order to create and adapt new systems to the recent Appendix O FAR 25 Aeronautical aircraft icing regulations. One important issue are the Supercooled Large Droplets (SLD) that are an important hazard in many cases. Novel sensor technologies for aircraft are being developed in order to assess the ice severity and to discriminate between large size droplets and small size droplets ice accretions. The European SENS4ICE project gives founding for the research and development of several aeronautical ice detection systems that can discriminate between Appendix C and Appendix O conditions. In the present paper, the strengths and weaknesses of the Fiber Optic ice Detector (FOD) developed by INTA are discussed using a test matrix from the Canadian National Research Council (NRC). The FOD has presented good performance at the NRC ice wind tunnel tests in the ice detection time, detecting ice in most cases earlier than required by the actual standard (ED-103). Its lightness, low intrusiveness and small size, makes the FOD ideal for aeronautical applications. It measures indirectly the icing cloud characteristics, such as the liquid water content (LWC) and the ice accretion rate, so only an approximate severity assessment could be done. • FBG sensors are useful for fast detection. • The Optic Fiber sensors can estimate the icing conditions in rime conditions • The optic fiber sensor can provide of information about the type of ice and its location

Informing care pathways and policies for children and youth with Indigenous perspectives to advance Canada's National Autism Strategy.

In Canada, most services for Autistic people are provided by provincial and territorial governments. However, support for Indigenous Peoples (First Nations, Inuit, and Métis) are under federal responsibility and are outlined by a set of treaties and agreements with the Crown and a few regional governments. This patchwork results in barriers in service access and navigation challenges in many under-resourced communities, including under-diagnosis and potentially life-threatening outcomes. Designing equitable policy structures and processes would reduce harms and meaningfully interface with Indigenous and other racialized communities. The objective of this Policy Practice Review is to provide a framework for the discovery of appropriate care strategies addressing the conceptualization of autism in Indigenous Peoples and to understand the interactions between racialized Autistic peoples and the Criminal Justice System. First, we conducted environmental scans of publicly-accessible government services available in Canada pertaining to autism in Indigenous communities and the justice system, and explored the dissonance with beliefs and perceptions of autism in Northern Indigenous communities. Second, we focused on the interactions of Indigenous and other racialized populations, with an emphasis on Autistic children and youth with the justice system, an interaction that is often life-altering, downstream, and detrimental to health and wellbeing. The implications of this work include identifying the need for Indigenous-led knowledge and policy recommendations for Canada's upcoming National Autism Strategy, informing the need for culturally appropriate multidisciplinary care and facilitating the coordination between health and social services for these communities.

International Graduate Students’ Mental Health Diagnoses, Challenges, and Support

Although there is a growing body of research that suggests the mental health of graduate students differs from that of their undergraduate counterparts, studies examining international students at the graduate level are scarce. This study therefore compares mental health diagnoses, challenges and stressors experienced, and use of mental health support, of international and non-international students who identified as being graduate/professional students. Data from the 2019 Canadian National College Health Assessment were used to compare the international graduate students (n = 1,876) to their non-international peers (n = 4,809). Significant differences were found on prevalence of conditions, certain specific challenges that are experienced, and help-seeking behaviours. Overall, international and non-international students may experience similar challenges, but international students are less likely to seek support. The findings suggest a need for graduate advisors and student affairs professionals to recognize the unique experiences of international graduate students particularly with their help-seeking behaviours.

Molecular identification of Cryptosporidium species in Canadian post-weaned calves and adult dairy cattle.

Cryptosporidium is a zoonotic protozoan parasite that is distributed globally and impacts both human and animal health. There are over 40 species of Cryptosporidium described to date, of which four (C. parvum, C. bovis, C. ryanae and C. andersoni) are routinely reported in cattle. The goal of this study was to identify the Cryptosporidium species infecting dairy cattle from across Canada using cow fecal samples and post-weaned calf rectal swabs obtained through the Canadian National Dairy Study. A total of 353 cattle samples (117 pooled rectal fecal swabs from post-weaned calves and 236 cow fecal samples) from 175 herds across the 10 Canadian provinces were analysed by targeting Cryptosporidium's small subunit ribosomal RNA (SSU rRNA or 18S) gene. Herd prevalence of Cryptosporidium was 27.4% nationally, ranging from 0% in Saskatchewan (SK) to 62% in Prince Edward Island (PE). The national prevalence of Cryptosporidium cattle infections was 15.4% in pooled rectal fecal swab samples from post-weaned calves and 16.1% in adult cows. Sanger sequence analysis of the SSU rRNA gene target revealed that C. bovis, C. andersoni and C. ryanae occurred in both adults and post-weaned calves, with C. bovis as the predominant species detected in pooled fecal swab samples of post-weaned calves (9/18, 50%) and C. andersoni as the predominant species in cows (25/38, 66%). Cryptosporidium parvum was not observed in any of the pooled rectal swab samples from post-weaned calves but was observed in one mixed infection of C. bovis/C. parvum in an adult cow. The fifth species identified in this study was C. muris and was present in two adult cows. Low concentrations of oocyst equivalents, as measured by quantitative real-time PCR (qPCR) of the SSU rRNA gene copy number, were observed in a subset of cattle samples. Cryptosporidium andersoni concentrations varied from province to province, with the widest range and highest counts in cows from PE. In conclusion, oocysts from Cryptosporidium species observed in this study are shed into the environment, contributing to the environmental load. However, the Cryptosporidium species in the post-weaned calves and cows found in this study pose a lower risk to the dairy cattle than if they were infected with C. parvum. Similarly, these Cryptosporidium species pose only a small risk to public health as the three species are infrequently reported in humans globally and have not been reported in Canadians to date.

Six new species of the genus Eumerus Meigen, 1822 from Iran (Diptera, Syrphidae)

1- Insect Taxonomy Research Department, Iranian Research Institute of Plant Protection (IRIPP), Agricultural Research, Education and Extension Organization (AREEO), Tehran, 19395–1454, Iran. , egilasian@yahoo.com 2- Syrphidae Foundation, Hof der Toekomst 48, 3823 HX Amersfoort, The Netherlands. 3- Canadian National Collection of Insects, Arachnids and Nematodes, Agriculture and Agri-Food Canada, 960 Carling Avenue, K.W.Neatby Building, Ottawa, ON, K1A 0C6, Canada.

Legal and Social Aspects of the Belarusian Economic Emigration to Canada in the 1920s-30s

The author examines the main features for the formation of the Belarusian economic emigration to Canada. The intensity of the emigration from 1921 to 1939 was analyzed, when the territory of Western Belarus was a part of Poland. The historical base of the research was the unpublished documents of the Belarusian, Ukrainian and Polish archives. The article presents the structure of state emigration bodies that were involved in organizing and controlling the recruitment of emigrants, their employment and the process of re-emigration. It describes the features of the Canadian legislation for the scale of the Belarusian emigration and the legal adaptation of emigrants. Particular attention is paid to the role of the Canadian railway companies “Canadian National Railways” and “Canadian Pacific Railways” in the selection of emigrants and their employment in agriculture and industry. The author argue that the Polish authorities stimulated the emigration of the Belarusian population for the polonization of Western Belarus. The problematic socio-psychological adaptation of the Belarusian emigrants, because Belarusians in Canada weakly expressed the national identity, is described. The author concludes that the international cooperation had an important role in forming the diaspora’s and national identity, especially the international contacts with the representatives of other peoples and the participation in common political organizations and projects.

Rating Health and Rating Change: How Canadians Rate Their Health and Its Changes.

Objectives: We investigated the contribution of five health domains to self-rated health (SRH) cross-sectionally and longitudinally and whether these contributions differ by gender or age. Methods: Employing dominance analyses, we quantified the contributions of functioning, diseases, pain, mental health, and behavior to both SRH at a point in time and for changes in SRH using data from the Canadian National Population Health Survey (NPHS, 1994-2011). Results: Cross-sectionally and longitudinally, functioning was the most important health domain, followed by diseases and pain. There were no meaningful differences in the ranking by gender while functioning, diseases, and pain were more relevant in older cohorts. Discussion: Functioning, diseases, and pain systematically were the most important health domains in both cross-sectional and longitudinal analyses. While these results held for women and men, they were more salient for older adults. This points to a gender-invariant but age-graded process, confirming previous research with European data.

Safety of mRNA COVID-19 vaccines during pregnancy

Safety of mRNA COVID-19 vaccines during pregnancy

Safety of COVID-19 vaccines in pregnancy: a Canadian National Vaccine Safety (CANVAS) network cohort study

BackgroundPregnant individuals have been receiving COVID-19 vaccines following pre-authorisation clinical trials in non-pregnant people. This study aimed to determine the frequency and nature of significant health events among pregnant females after COVID-19 vaccination, compared with unvaccinated pregnant controls and vaccinated non-pregnant individuals.MethodsWe did an observational cohort study, set in seven Canadian provinces and territories including Ontario, Quebec, British Columbia, Alberta, Nova Scotia, Yukon, and Prince Edward Island. Eligibility criteria for vaccinated individuals were a first dose of a COVID-19 vaccine within the previous 7 days; an active email address and telephone number; ability to communicate in English or French; and residence in the aforementioned provinces or territories. Study participants were pregnant and non-pregnant females aged 15–49 years. Individuals were able to participate as controls if they were unvaccinated and fulfilled the other criteria. Data were collected primarily by self-reported survey after both vaccine doses, with telephone follow-up for those reporting any medically attended event. Participants reported significant health events (new or worsening of a health event sufficient to cause work or school absenteeism, medical consultation, or prevent daily activities) occurring within 7 days of vaccination or within the past 7 days for unvaccinated individuals. We employed multivariable logistic regression to examine significant health events associated with mRNA vaccines, adjusting for age group, previous SARS-CoV-2 infection, and trimester, as appropriate.FindingsAs of Nov 4, 2021, 191 360 women aged 15–49 years with known pregnancy status had completed the first vaccine dose survey and 94 937 had completed the second dose survey. 180 388 received one dose and 94 262 received a second dose of an mRNA vaccine, with 5597 pregnant participants receiving dose one and 3108 receiving dose two, and 174 765 non-pregnant participants receiving dose one and 91 131 receiving dose two. Of 6179 included unvaccinated control participants, 339 were pregnant and 5840 were not pregnant. Overall, 226 (4·0%) of 5597 vaccinated pregnant females reported a significant health event after dose one of an mRNA vaccine, and 227 (7·3%) of 3108 after dose two, compared with 11 (3·2%) of 339 pregnant unvaccinated females. Pregnant vaccinated females had an increased odds of a significant health event within 7 days of the vaccine after dose two of mRNA-1273 (adjusted odds ratio [aOR] 4·4 [95% CI 2·4–8·3]) compared with pregnant unvaccinated controls within the past 7 days, but not after dose one of mRNA-1273 or any dose of BNT162b2. Pregnant vaccinated females had decreased odds of a significant health event compared with non-pregnant vaccinated females after both dose one (aOR 0·63 [95% CI 0·55–0·72]) and dose two (aOR 0·62 [0·54–0·71]) of any mRNA vaccination. There were no significant differences in any analyses when restricted to events which led to medical attention.InterpretationCOVID-19 mRNA vaccines have a good safety profile in pregnancy. These data can be used to appropriately inform pregnant people regarding reactogenicity of COVID-19 vaccines during pregnancy, and should be considered alongside effectiveness and immunogenicity data to make appropriate recommendations about best use of COVID-19 vaccines in pregnancy.FundingCanadian Institutes of Health Research, Public Health Agency of Canada.

The load planning and sequencing problem for double-stack trains

This paper addresses the integrated load planning and sequencing problem (LPSP) for double-stack trains. This decision-making problem occurs in intermodal terminals and consists in assigning containers from a storage area to slots on railcars of outbound trains and in determining the loading sequence of the handling equipment. Even though this a relevant operational problem, it has seen no attention in the operations research literature so far. Prior models either focus on single-stack railcars or treat the load planning and sequencing separately. By extending prior work on load planning, we propose two different integer linear programming formulations. We show by an extensive numerical study that we are able to solve instances with up to 50 containers with a commercial general-purpose solver in less than 20 min. A case study based on real data provided by the Canadian National Railway Company highlights that the LPSP can reduce the number of container handlings in intermodal terminals compared to sequential solutions by on average 11.3% and 16.5% for gantry cranes and reach stackers, respectively.

Monitoring Variables Influence on Random Forest Models to Forecast Injuries in Short-Track Speed Skating.

Injuries limit the athletes' ability to participate fully in their training and competitive process. They are detrimental to performance, affecting the athletes psychologically while limiting physiological adaptations and long-term development. This study aims to present a framework for developing random forest classifier models, forecasting injuries in the upcoming 1 to 7 days, to assist the performance support staff in reducing injuries and maximizing performance within the Canadian National Female Short-Track Speed Skating Program. Forty different variables monitored daily over two seasons (2018–2019 and 2019–2020) were used to develop two sets of forecasting models. One includes only training load variables (TL), and a second (ALL) combines a wide array of monitored variables (neuromuscular function, heart rate variability, training load, psychological wellbeing, past injury type, and location). The sensitivity (ALL: 0.35 ± 0.19, TL: 0.23 ± 0.03), specificity (ALL: 0.81 ± 0.05, TL: 0.74 ± 0.03) and Matthews Correlation Coefficients (MCC) (ALL: 0.13 ± 0.05, TL: −0.02 ± 0.02) were computed. Paired T-test on the MCC revealed statistically significant (p < 0.01) and large positive effects (Cohen d > 1) for the ALL forecasting models' MCC over every forecasting window (1 to 7 days). These models were highly determined by the athletes' training completion, lower limb and trunk/lumbar injury history, as well as sFatigue, a training load marker. The TL forecasting models' MCC suggests they do not bring any added value to forecast injuries. Combining a wide array of monitored variables and quantifying the injury etiology conceptual components significantly improve the injury forecasting performance of random forest models. The ALL forecasting models' performances are promising, especially on one time windows of one or two days, with sensitivities and specificities being respectively above 0.5 and 0.7. They could add value to the decision-making process for the support staff in order to assist the Canadian National Female Team Short-Track Speed Skating program in reducing the number of incomplete training days, which could potentially increase performance. On longer forecasting time windows, ALL forecasting models' sensitivity and MCC decrease gradually. Further work is needed to determine if such models could be useful for forecasting injuries over three days or longer.

Adolescent and young adult (AYA) oncology: A credentialed area of focused competence in Canada.

Adolescents and young adults (AYA, ages 15-39 years) affected by cancer have unique treatment, survivorship, and palliation concerns. Current oncology training does not focus on the distinctive needs of this demographic. Amid this recognition, the Canadian National AYA Cancer Task Force and Canadian Partnership Against Cancer have advocated the need for clinicians with formalized AYA experience. To address this need and standardize training, a national task force developed criteria for structured academic programs in AYA Oncology in Canada. Workshops were organized to identify and establish the fundamentals of practice in AYA Oncology through consensus. These workshops followed the pre-existing rigorous process established by the Royal College of Physicians and Surgeons of Canada (Royal College) for new program development. The process includes: (i) developing the tasks associated with the discipline's practice, (ii) identifying the evidence trainees must provide to demonstrate tasks can be performed independently (the competence portfolio), (iii) developing training requirements and summarizing the knowledge, skills and attitudes required to perform these tasks, and (iv) identifying specific experiences essential to acquiring skills and demonstrating competent performance. AYA Oncology is a recognized an Area of Focused Competence (AFC) by the Royal College. The AFC designation in AYA Oncology provides a standardized curriculum, training experience and accreditation process to attract oncologists, promote expertise and advance AYA oncology care.

Equity in the use of physician services in Canada's universal health system: A longitudinal analysis of older adults

This study presents longitudinal evidence on the trends and determinants of income-related inequities in general practitioner (GP), specialist, and any physician visits among older adults (aged 65+) in Canada. Using the Canadian National Population Health Survey between 1998/99 and 2010/11, random effect probit and negative binomial models were employed to model the probability of visit and the total number of visits, respectively. The concentration index-based horizontal inequity (HI) approach was used to measure income-related inequities in physician services. The decomposition technique was applied to explain the factors contributing to the observed inequities. The mobility index (MI) was also calculated to compare short-run and long-run estimates of inequities. The HI indices reveal significant pro-rich inequities in both the probability and the number of specialist visits. Inequities in the likelihood of GP visits and any physician visits were pro-rich but trivial in magnitude. The MI shows that upwardly income mobile individuals contribute to inequity in specialist visits in the long run. After income, education was the most important contributor to inequity in specialist visits, while unobserved heterogeneity explained most of the pro-rich inequity in the total number of GP and any physician visits. Although physician services are free at the point of the provision in Canada, this study demonstrates that poorer older adults utilized fewer specialist services than richer older adults for the same level of need. Specific policies are needed to ensure equity in specialist care use among the older adults in Canada.

Serious Scientific Flaws in the Canadian National Breast Screening Study Trials Revealed in a Report from Breast Cancer Screening Experts.

HomeRadiology: Imaging CancerVol. 4, No. 4 Previous Research HighlightsSerious Scientific Flaws in the Canadian National Breast Screening Study Trials Revealed in a Report from Breast Cancer Screening ExpertsBonnie N. Joe, Samantha Fung-LeeBonnie N. Joe, Samantha Fung-LeeBonnie N. JoeSamantha Fung-LeePublished Online:Jul 29 2022https://doi.org/10.1148/rycan.229017MoreSectionsFull textPDF ToolsImage ViewerAdd to favoritesCiteTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked In Highlighted ArticleSeely JM, Eby PR, Yaffe MJ. The fundamental flaws of the CNBSS trials: a scientific review. J Breast Imaging 2022;4(2):108–112.doi: https://doi.org/10.1093/jbi/wbab099 Crossref, Google ScholarArticle HistoryPublished online: July 29 2022 FiguresReferencesRelatedDetailsRecommended Articles Closing the Gap: Disparities in Breast Cancer Mortality among African American WomenRadiology: Imaging Cancer2020Volume: 2Issue: 5Non-BRCA Early-Onset Breast Cancer in Young WomenRadioGraphics2022Volume: 42Issue: 1pp. 5-22Lessons Learned from the Randomized Controlled TOmosynthesis plus SYnthesized MAmmography (TOSYMA) TrialRadiology2022Volume: 306Issue: 2Breast Cancer Screening in High-Risk Men: A 12-year Longitudinal Observational Study of Male Breast Imaging Utilization and OutcomesRadiology2019Volume: 293Issue: 2pp. 282-291Predicting Breast Cancer by Applying Deep Learning to Linked Health Records and MammogramsRadiology2019Volume: 292Issue: 2pp. 331-342See More RSNA Education Exhibits An Educational Perspective: Surveillance Following Breast Conservation TherapyDigital Posters2019Artificial Intelligence in an Era of Increasing Global Cancer Burden: Opportunities and Challenges for Breast Cancer in Low- and Middle-Income CountriesDigital Posters2020Let’s Talk about Next-Generation Breast Cancer Screening Programs: How Should We Do? What Should We Use?Digital Posters2020 RSNA Case Collection Male invasive Ductal Carcinoma RSNA Case Collection2022Lactating BreastRSNA Case Collection2022Recurrent breast cancer on CEUSRSNA Case Collection2021 Vol. 4, No. 4 Metrics Altmetric Score PDF download

Extending the National Burned Area Composite Time Series of Wildfires in Canada

Wildfires are a major natural disturbance in Canada that are postulated to increase under a warming climate. To derive accurate trends in burned area and to quantify the effects of fire frequency, duration, and extent, a sufficiently long time series of reliable burned area maps is required. With that in mind, we extended Canada’s National Burned Area Composite (NBAC) dataset from its previous start year (2004) back to 1986. NBAC consists of annual maps in polygon format where the area burned in each fire event is represented by the best available delineation among various mapping methods and data sources of varying quality. Ordered from more to less reliability, in the new 35-year time series (1986 to 2020), 10% of the total burned area was derived from airborne and high-resolution (&lt;5 m) satellite imagery, 81% from change detection methods using 30 m Landsat satellite imagery, and the remaining 9% was largely from aerial surveys. Total (Canada-wide) annual burned area estimates ranged from 215,797 ha in 2020 to 6.7 million ha (Mha) in 1989. We computed 95% confidence intervals for the estimate of each year from 1986 to 2020 based on the accuracy and relative contribution in that year of the different data sources, for both the new NBAC time series and the polygon version of the Canadian National Fire Database (CNFDB), a commonly used source of spatially explicit data on burned area in Canada. NBAC confidence intervals were on average ±9.7% of the annual figure, about one-third the width of the confidence intervals derived for CNFDB. The NBAC time series also included nearly 5000 fire events (totalling 4 Mha, with the largest event being 120,661 ha in size) that are missing in the CNFDB. In a regional analysis for the Northwest Territories, retroactive fire mapping from Landsat imagery reduced historical estimates by 3 Mha (16%), which would result in a 1.6 Mha increase in the reported undisturbed critical habitat for threatened woodland caribou. The NBAC dataset is freely downloadable from the Canadian Wildland Fire Information System.