Browsing by Author "Naugler, Christopher"
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- ItemOpen AccessAnalysis of Alternatives and Performance Evaluation Using a New OWA Operator based on the Laplace Distribution(2016) Mohammed, Emad; Far, Behrouz; Naugler, Christopher; Moussavi, Mahmood; Eberlien, Armin; Zareipour, Hamid; Sadaoui, SamiraAnalysis of Alternatives (AoA) is an assessment of operational effectiveness, appropriateness, cost, and risk associated with alternative solutions to specific problem requirements. Decision makers can utilize the AoA outcome to support their informed decisions that favor a specific alternative. Multiple criteria decision-making (MCDM) denotes the act of choosing, implementing, and applying a specific course of action to solve problems based on the AoA result of the multiple criteria alternatives. An intrinsic characteristic of the criteria is their conflicting nature, i.e., some criteria are more appealing than others for different decision makers, and thus, the selection process of the best alternative is vastly dependent on the decision makers’ preferences. This introduces discrepancy in the AoA process, which results from systematic errors introduced by the decision makers. This is common in a typical group decision-making scenario where many individuals are involved in the decision process, and thus, a method to aggregate the different evaluation viewpoints is mandatory. The ordered weighted averaging (OWA) operator is a mapping function that is used to aggregate different viewpoints. This thesis describes a new method to calculate the weight vector of the OWA operator based on the Laplace distribution. The proposed OWA operator is a new method for AoA to minimize discrepancy in alternative assessment, e.g., disagreement on the weight vector that leads to higher scores for the appealing criteria and smaller scores for the less interesting ones. The proposed OWA operator assigns smaller weights to both the higher and smaller scores, and thus, reduces the discrepancy in the AoA process. To prove the usefulness of the proposed operator, the calculated score is utilized in machine learning models as an explanatory variable for regression and classification problems and the results are compared to other OWA operators. The proposed OWA operator outperforms other operators in a breast cancer classification problem with an accuracy of 99.71%. Furthermore, a new model based on the calculated score and the Z-score is proposed for alternatives performance evaluation. The results of this method are illustrated using a case study for used cars performance ranking and evaluation with sensitivity analysis.
- ItemOpen AccessAssessing the research landscape and clinical utility of large language models: a scoping review(2024-03-12) Park, Ye-Jean; Pillai, Abhinav; Deng, Jiawen; Guo, Eddie; Gupta, Mehul; Paget, Mike; Naugler, ChristopherAbstract Importance Large language models (LLMs) like OpenAI’s ChatGPT are powerful generative systems that rapidly synthesize natural language responses. Research on LLMs has revealed their potential and pitfalls, especially in clinical settings. However, the evolving landscape of LLM research in medicine has left several gaps regarding their evaluation, application, and evidence base. Objective This scoping review aims to (1) summarize current research evidence on the accuracy and efficacy of LLMs in medical applications, (2) discuss the ethical, legal, logistical, and socioeconomic implications of LLM use in clinical settings, (3) explore barriers and facilitators to LLM implementation in healthcare, (4) propose a standardized evaluation framework for assessing LLMs’ clinical utility, and (5) identify evidence gaps and propose future research directions for LLMs in clinical applications. Evidence review We screened 4,036 records from MEDLINE, EMBASE, CINAHL, medRxiv, bioRxiv, and arXiv from January 2023 (inception of the search) to June 26, 2023 for English-language papers and analyzed findings from 55 worldwide studies. Quality of evidence was reported based on the Oxford Centre for Evidence-based Medicine recommendations. Findings Our results demonstrate that LLMs show promise in compiling patient notes, assisting patients in navigating the healthcare system, and to some extent, supporting clinical decision-making when combined with human oversight. However, their utilization is limited by biases in training data that may harm patients, the generation of inaccurate but convincing information, and ethical, legal, socioeconomic, and privacy concerns. We also identified a lack of standardized methods for evaluating LLMs’ effectiveness and feasibility. Conclusions and relevance This review thus highlights potential future directions and questions to address these limitations and to further explore LLMs’ potential in enhancing healthcare delivery.
- ItemOpen AccessClinical Decision Support System with Adaptive Software Framework for Chronic Lymphocytic Leukaemia Cell Classification(2013-09-16) Mohammed, Emad; Far, Behrouz; Naugler, ChristopherThis thesis presents a new clinical decision support system (CDSS), which operates within an adaptive software framework and a tailored wrapper design pattern for chronic lymphocytic leukaemia (CLL) cell classification. The system goes through a sequence of steps while working with the lymphocyte images: it segments the lymphocyte with average segmentation accuracy of (97% ±0.5 for lymphocyte nucleus and 92.08% ±9.24 for lymphocyte cytoplasm); it extracts features; it selects from those features the relevant ones; and, it then classifies the selected features. The proposed system composite classifier model has a trust factor of 84.16%, accuracy of 87.0%, 84.95% true positive rate, and 10.96% false positive rate. The framework along with the wrapper pattern became a generic interface for any new algorithm. The framework built on top of the data-centric architecture which provides a great flexibility to the system design. The wrapper verifies the new algorithm interface against built-in test procedures.
- ItemOpen AccessCommunity Fecal Immunotesting for Colorectal Cancer Screening(2015-04-02) Crouse, Amber; Naugler, ChristopherCommunity fecal immunochemical testing screening programs are important for detecting early disease and are a common way of promoting colorectal cancer screening by primary care physicians. Fecal Immunochemical testing has advantages to the patient as well as to clinical laboratories, but screening rates remain low across Canada and may be associated with sociodemographic factors. This research assesses the operational test characteristics of a FIT pilot program in Calgary, Alberta. Data from a new community-based screening program were also used to test associations of screening rate with sociodemographic variables. The performance of FIT in this clinical setting was very good for detecting carcinoma, but marginal for detection of colonic adenomas. There was also significant geographic variation in screening rates in Calgary. These are associated with a number of sociodemographic factors.
- ItemOpen AccessCorrection to: Family Integrated Care (FICare) in Level II Neonatal Intensive Care Units: study protocol for a cluster randomized controlled trial(2020-03-19) Benzies, Karen M; Shah, Vibhuti; Aziz, Khalid; Isaranuwatchai, Wanrudee; Palacio-Derflingher, Luz; Scotland, Jeanne; Larocque, Jill; Mrklas, Kelly; Suter, Esther; Naugler, Christopher; Stelfox, Henry T; Chari, Radha; Lodha, AbhayAfter publication of our article [1], the authors have reported mathematical errors made in the sample size calculation for this cluster randomized controlled trial (cRCT) (Benzies et al. 2017).
- ItemEmbargoDifficulty in Transitioning from Medical Residency to Independent Practice in Pathology(2024-04-26) Ayala, Gabriel Eduardo; Naugler, Christopher; Sidhu, Davinder; Ismail, ZahinoorTransitioning from residency to medical independent medical practice may be a difficult experience for physicians. In this thesis, I explore this issue amongst Canadian Pathologists through an online survey of 118 practicing pathologists and 11 follow-up in-depth one-on-one interviews. Survey results revealed that only 40% of participants reported that they did not experience difficulty transitioning to independent practice. I used a mixed methods approach to determine themes associated with difficulty transitioning. I then developed a psychological traits profile for pathologists based on the Big 5 psychological traits and looked for differences in psychological profiles between individuals who reported difficulty and those who did not. Only minor differences were observed. The biggest predictor of difficulty transitioning was the Royal College specialty with Anatomic Pathologists experiencing significantly more difficulty than General Pathologists. This difference may relate to increased opportunity for graded responsibility in General Pathology residency training programs. Finally, I explored the way pathology residents perceive different forms of feedback and offered recommendations to residency training programs on ways that feedback could be optimized to best support the transition to independent practice.
- ItemOpen AccessDigital Imaging in Pathology(2014-05-02) Horn, Christopher Lee; Naugler, ChristopherA large component of pathology informatics is the usage and utility of digital images. The main objectives of this thesis involve many different applications related to digital imaging and anatomic pathology. An initial literature review identifies the delivery and applications of digital images and current imaging systems related to pathology including hematopathology, and whole slide imaging platforms. Telepathology as the future delivery model of pathology digital images is examined as well. Pathology staff across Canada currently utilizes gross digital images for regular documentation and educational reasons. They also indicate that the technology will be needed for future applications in teaching, consultation and medico-legal purposes. Currently, there is no resource available to match up typical gross features with the appropriate gross descriptive term. This is accomplished in this thesis and can be used as an educational tool for pathology professionals.
- ItemOpen AccessEffectiveness of Alberta Family Integrated Care on infant length of stay in level II neonatal intensive care units: a cluster randomized controlled trial(2020-11-28) Benzies, Karen M; Aziz, Khalid; Shah, Vibhuti; Faris, Peter; Isaranuwatchai, Wanrudee; Scotland, Jeanne; Larocque, Jill; Mrklas, Kelly J; Naugler, Christopher; Stelfox, H. T; Chari, Radha; Soraisham, Amuchou S; Akierman, Albert R; Phillipos, Ernest; Amin, Harish; Hoch, Jeffrey S; Zanoni, Pilar; Kurilova, Jana; Lodha, AbhayAbstract Background Parents of infants in neonatal intensive care units (NICUs) are often unintentionally marginalized in pursuit of optimal clinical care. Family Integrated Care (FICare) was developed to support families as part of their infants’ care team in level III NICUs. We adapted the model for level II NICUs in Alberta, Canada, and evaluated whether the new Alberta FICare™ model decreased hospital length of stay (LOS) in preterm infants without concomitant increases in readmissions and emergency department visits. Methods In this pragmatic cluster randomized controlled trial conducted between December 15, 2015 and July 28, 2018, 10 level II NICUs were randomized to provide Alberta FICare™ (n = 5) or standard care (n = 5). Alberta FICare™ is a psychoeducational intervention with 3 components: Relational Communication, Parent Education, and Parent Support. We enrolled mothers and their singleton or twin infants born between 32 0/7 and 34 6/7 weeks gestation. The primary outcome was infant hospital LOS. We used a linear regression model to conduct weighted site-level analysis comparing adjusted mean LOS between groups, accounting for site geographic area (urban/regional) and infant risk factors. Secondary outcomes included proportions of infants with readmissions and emergency department visits to 2 months corrected age, type of feeding at discharge, and maternal psychosocial distress and parenting self-efficacy at discharge. Results We enrolled 654 mothers and 765 infants (543 singletons/111 twin cases). Intention to treat analysis included 353 infants/308 mothers in the Alberta FICare™ group and 365 infants/306 mothers in the standard care group. The unadjusted difference between groups in infant hospital LOS (1.96 days) was not statistically significant. Accounting for site geographic area and infant risk factors, infant hospital LOS was 2.55 days shorter (95% CI, − 4.44 to − 0.66) in the Alberta FICare™ group than standard care group, P = .02. Secondary outcomes were not significantly different between groups. Conclusions Alberta FICare™ is effective in reducing preterm infant LOS in level II NICUs, without concomitant increases in readmissions or emergency department visits. A small number of sites in a single jurisdiction and select group infants limit generalizability of findings. Trial registration ClinicalTrials.gov Identifier NCT02879799 , retrospectively registered August 26, 2016.
- ItemOpen AccessEvaluating the coding accuracy of type 2 diabetes mellitus among patients with non-alcoholic fatty liver disease(2024-02-16) Lee, Seungwon; Shaheen, Abdel A.; Campbell, David J. T.; Naugler, Christopher; Jiang, Jason; Walker, Robin L.; Quan, Hude; Lee, JoonAbstract Background Non-alcoholic fatty liver disease (NAFLD) describes a spectrum of chronic fattening of liver that can lead to fibrosis and cirrhosis. Diabetes has been identified as a major comorbidity that contributes to NAFLD progression. Health systems around the world make use of administrative data to conduct population-based prevalence studies. To that end, we sought to assess the accuracy of diabetes International Classification of Diseases (ICD) coding in administrative databases among a cohort of confirmed NAFLD patients in Calgary, Alberta, Canada. Methods The Calgary NAFLD Pathway Database was linked to the following databases: Physician Claims, Discharge Abstract Database, National Ambulatory Care Reporting System, Pharmaceutical Information Network database, Laboratory, and Electronic Medical Records. Hemoglobin A1c and diabetes medication details were used to classify diabetes groups into absent, prediabetes, meeting glycemic targets, and not meeting glycemic targets. The performance of ICD codes among these groups was compared to this standard. Within each group, the total numbers of true positives, false positives, false negatives, and true negatives were calculated. Descriptive statistics and bivariate analysis were conducted on identified covariates, including demographics and types of interacted physicians. Results A total of 12,012 NAFLD patients were registered through the Calgary NAFLD Pathway Database and 100% were successfully linked to the administrative databases. Overall, diabetes coding showed a sensitivity of 0.81 and a positive predictive value of 0.87. False negative rates in the absent and not meeting glycemic control groups were 4.5% and 6.4%, respectively, whereas the meeting glycemic control group had a 42.2% coding error. Visits to primary and outpatient services were associated with most encounters. Conclusion Diabetes ICD coding in administrative databases can accurately detect true diabetic cases. However, patients with diabetes who meets glycemic control targets are less likely to be coded in administrative databases. A detailed understanding of the clinical context will require additional data linkage from primary care settings.
- ItemOpen AccessFamily Integrated Care (FICare) in Level II Neonatal Intensive Care Units: study protocol for a cluster randomized controlled trial(2017-10-10) Benzies, Karen M; Shah, Vibhuti; Aziz, Khalid; Isaranuwatchai, Wanrudee; Palacio-Derflingher, Luz; Scotland, Jeanne; Larocque, Jill; Mrklas, Kelly; Suter, Esther; Naugler, Christopher; Stelfox, Henry T; Chari, Radha; Lodha, AbhayAbstract Background Every year, about 15 million of the world’s infants are born preterm (before 37 weeks gestation). In Alberta, the preterm birth rate was 8.7% in 2015, the second highest among Canadian provinces. Approximately 20% of preterm infants are born before 32 weeks gestation (early preterm), and require care in a Level III neonatal intensive care unit (NICU); 80% are born moderate (32 weeks and zero days [320/7] to 336/7 weeks) and late preterm (340/7 to 366/7 weeks), and require care in a Level II NICU. Preterm birth and experiences in the NICU disrupt early parent-infant relationships and induce parental psychosocial distress. Family Integrated Care (FICare) shows promise as a model of care in Level III NICUs. The purpose of this study is to evaluate length of stay, infant and maternal clinical outcomes, and costs following adaptation and implementation of FICare in Level II NICUs. Methods We will conduct a pragmatic, cluster randomized controlled trial (cRCT) in ten Alberta Level II NICUs allocated to one of two groups: FICare or standard care. The FICare Alberta model involves three theoretically-based, standardized components: information sharing, parenting education, and family support. Our sample size of 181 mother-infant dyads per group is based on the primary outcome of NICU length of stay, 80% participation, and 80% retention at follow-up. Secondary outcomes (e.g., infant clinical outcomes and maternal psychosocial distress) will be assessed shortly after admission to NICU, at discharge and 2 months corrected age. We will conduct economic analysis from two perspectives: the public healthcare payer and society. To understand the utility, acceptability, and impact of FICare, qualitative interviews will be conducted with a subset of mothers at the 2-month follow-up, and with hospital administrators and healthcare providers near the end of the study. Discussion Results of this pragmatic cRCT of FICare in Alberta Level II NICUs will inform policy decisions by providing evidence about the clinical effectiveness and costs of FICare. Trial registration ClinicalTrials.gov, ID: NCT02879799 . Registered on 27 May 2016. Protocol version: 9 June 2016; version 2.
- ItemOpen AccessFast Food and Presumptive Heart Attack in Calgary, Canada(2015-04-29) Dupuis, Barbara A.; Sandalack, Beverly; Naugler, ChristopherMethod: Patients with heart attack were identified in the Calgary Laboratory Services database as having a blood test with a critical value indicating heart attack. A second group of participants with no heart issues were identified in the same database and matched to the heart attack group by age and sex at a 1:4 ratio. All participants were mapped in a mapping program and individual level information about the density and distance to fast food outlets was collected. This geographic data was exported for statistical analysis. Results: If the density of fast food within 1000 meters is above average a participant is 1.226 times more likely to have a presumptive heart attack than participants with exposures less than average. Conclusions: More study is required to determine if this relationship is time dependent and whether this relationship is also affected by fast food around workplaces.
- ItemOpen AccessIncidence of acute lymphocytic leukemia in Calgary, Alberta, Canada: a retrospective cohort study(2018-02-07) Snodgrass, Rayven; Nguyen, Leonard T; Guo, Maggie; Vaska, Marcus; Naugler, Christopher; Rashid-Kolvear, FariborzAbstract Objective Acute lymphocytic leukemia (ALL) is a rare malignant neoplasm that develops from abnormal lymphoid stem cells. ALL incidence is highest among children and declines towards adolescence. There is limited data on the epidemiology of ALL, especially in Canada. This retrospective cohort study used patient data from the Calgary Laboratory Services Cancer Cytogenetics Laboratory to report the incidence rate of ALL in Calgary, Alberta, Canada. New cases of ALL were identified for the 5-year period of January 1, 2011 until December 31, 2015. Reported incidence rates were categorized by sex and age groups, and age-standardized to the Canadian population. Results There were an average of 11.4 new cases of ALL diagnosed per year between 2011 and 2015. The total incidence rate per 100,000 person-years was 0.84. Incidence rates peaked in children aged 0–4 with 7.55 and 3.32 cases per 100,000 person-years for males and females, respectively. The median age of diagnosis was 8 years. Incidence rates were generally lowest for adults aged 20 and over. The ratio of males to females diagnosed with ALL was 1.59. Overall, the recent incidence of ALL in Calgary is comparatively low with a preference for males and children below 5 years of age.
- ItemOpen AccessIncidence of chronic myeloid leukemia in Calgary, Alberta, Canada(2018-11-01) Nguyen, Leonard T; Guo, Maggie; Naugler, Christopher; Rashid-Kolvear, FariborzAbstract Objective The epidemiology of chronic myeloid leukemia is shifting due to the aging global population and the recent discovery and availability of targeted treatment options. This study provides recent data regarding the incidence of CML in Calgary, a major Canadian city. Data from patients diagnosed with CML by bone marrow sample analysis from 2011 to 2015 were collected from the database of the sole centralized cytogenetics facility in service of Calgary and its surrounding area. Results With an average of 10.2 newly diagnosed cases per year in Calgary from 2011 to 2015, the incidence rate was calculated to be 0.75 cases per 100,000 person-years (95% CI 0.57–0.99). With age standardization, the incidence was 0.87 cases per 100,000 person-years (95% CI 0.82–0.91) for the Canadian population, which was low compared to other developed Western nations. The highest incidence rates were observed in the older patient categories, however there was a broad age distribution for incident cases and the median age at diagnosis was 48. There was a general male bias for CML most pronounced at the younger ages. Our description of CML incidence will help to inform healthcare planners amidst the dramatically altered treatment of this hematological neoplasm.
- ItemOpen AccessIncidence of myeloproliferative neoplasms in Calgary, Alberta, Canada(2019-05-24) Heppner, Jonathan; Nguyen, Leonard T; Guo, Maggie; Naugler, Christopher; Rashid-Kolvear, FariborzAbstract Objective The incidence of the combined myeloproliferative neoplasms (MPNs) was determined for a major Canadian city. Retrospective cases of MPN diagnoses (essential thrombocythemia, polycythemia vera, and primary myelofibrosis) between 2011 to 2015 were retrieved from the Southern Alberta Cancer Cytogenetics Laboratory’s database at Alberta Public Laboratories. Results An incidence rate of 2.05 cases per 100,000 person-years (95% CI 1.73–2.41) was determined, giving an age-standardized Canadian incidence of 2.71 cases per 100,000 person years (95% CI 2.63–2.78). MPN diagnoses occurred at a wide age range of 8–93 (median 66) and an age-dependent increase in incidence. Incidence rates for the MPNs are first reported here for a Canadian population.
- ItemOpen AccessIron Deficiency, Iron Deficiency Anemia, and Infectious Disease in Calgary, Alberta(2021-12-20) Giacobbo, Olivia; Wilson, Warren; Naugler, Christopher; Steig, Johnson; Roshan, Tariq; Wilson, Warren; Naugler, ChristopherAn estimated 30% of the global population suffers from iron deficiency anemia (IDA) and previous studies have suggested that iron deficiency (ID) and IDA are associated with adverse health outcomes. However, some research suggests that ID and IDA may be adaptive in areas with high levels of endemic infectious diseases. The present study examined the association between serum iron levels and four infectious diseases in a sample of 55,437 individuals in Calgary, Alberta. Associations between sociodemographic variables (SDVs) and iron and infection were also tested to explore ID’s complex etiology. This study evaluates two hypotheses: HA1: Low baseline serum iron predicts a lower risk of infection up to one year out, and HA2: Sociodemographic variables (higher median income, more postsecondary education, non-immigrant status, and non-Indigenous status) will be associated with higher serum iron levels. Cox regression analyses found that the lowest levels of iron were predictive of greater risk for infection in sepsis (blood) and urinary tract infections. Iron level was not associated with fungal sepsis and strep throat. Multiple regression analyses found no significant relationships between infection and SDVs and found that greater median household income and postsecondary education level were associated with higher mean serum iron levels. This research emphasizes the importance of context when evaluating the adaptiveness of a trait, in addition to calling for further investigation into individual-level associations of sociodemographic variables and infection throughout the city of Calgary.
- ItemOpen AccessLaboratory Testing for Chronic Lymphocytic Leukemia(2015-06-03) Healey, Ryan Louis; Naugler, Christopher; Patel, JayThis thesis addresses two current issues in the laboratory diagnosis and understanding of chronic lymphocytic leukemia (CLL). Clinical laboratory testing by flow cytometry is critically important for the identification and characterization of CLL and other blood cancers. Flow cytometry investigations, however, are complex, time consuming, and financially costly. These factors drive the need for improvements in laboratory test utilization, particularly in publically funded healthcare systems and in resource-limited areas of the world. Several low-cost ancillary hematology and chemistry lab tests which are often performed alongside flow cytometry testing were investigated in order to identify biomarkers useful in the prediction of CLL or other similar leukemias. Using these predictors, a novel model is proposed for the triaging of bloods for flow cytometry. Diagnostic data was also used to ascertain the current incidence of CLL in the study cohort and standardized to the Canadian population.
- ItemOpen AccessProstate Specific Antigen Testing and Prostate Specific Antigen Velocity for the Screening of Prostate Cancer(2015-10-02) Gorday, William; Naugler, ChristopherProstate specific antigen (PSA) testing for the screening of prostate cancer is controversial with medical and governmental organizations issuing contradictory statements regarding its use. My research looked at the utilization of the PSA test for the screening of prostate cancer in Calgary, Alberta for 2011 and if sociodemographic factors influenced the rate of testing. I studied whether PSA velocity is better than a single PSA test in predicting prostate biopsy outcome and if sub-dividing Gleason score 7 prostate cancers improves the predictive ability of PSA tests. My research found that PSA testing does not follow official guidelines in younger men and that certain sociodemographic factors do influence the rate of PSA testing. I found that PSA velocity is not better than the PSA test in predicting prostate biopsy diagnosis and that sub-dividing Gleason score 7 prostate cancers can increase the clinical utility of the PSA test.
- ItemOpen AccessRefined Prognostication in Coronary Artery Disease Using Routine Laboratory Test Data(2016) Gerling, Michael; de Koning, Lawrence; James, Matthew; Naugler, Christopher; Wilton, StephenCoronary artery disease (CAD) is a leading cause of morbidity and mortality. Numerous prognostic scores have been developed that rely on clinical information to predict risk of adverse outcomes and subsequently aid clinicians in determining appropriate intervention strategies. This thesis examines the ability of laboratory test data, including the complete blood count (CBC), electrolytes, estimated glomerular filtration rate (eGFR), and 25-OH vitamin D, to improve prognostic assessment in CAD patients beyond existing clinical risk factors. Although 25-OH vitamin D status was found to be inversely associated with mortality, it was neither associated with nor predictive of hospital readmission, and provided little additional prognostic information beyond existing risk factors. Conversely, a risk score derived from components of the CBC, electrolytes, and eGFR, in conjunction with age and sex, was strongly predictive of mortality, and led to considerable improvement in the ability to identify high-risk patients beyond existing risk factors.
- ItemOpen AccessSociodemographic and geospatial associations with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections in a large Canadian city: an 11 year retrospective study(2019-07-09) Gill, Victoria C; Ma, Irene; Guo, Maggie; Gregson, Dan B; Naugler, Christopher; Church, Deirdre LAbstract Background The first Canadian outbreak of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) was identified in 2004 in Calgary, Alberta. Using a novel model of MRSA population-based surveillance, sociodemographic risk associations, yearly geospatial dissemination and prevalence of CA-MRSA infections over an 11 year period was identified in an urban healthcare jurisdiction of Calgary. Methods Positive MRSA case records, patient demographics and laboratory data were obtained from a centralized Laboratory Information System of Calgary Laboratory Services in Calgary, Alberta, Canada between 2004 and 2014. Public census data was obtained from Statistics Canada, which was used to match with laboratory data and mapped using Geographic Information Systems. Results During the study period, 52.5% of positive MRSA infections in Calgary were CA-MRSA cases. The majority were CMRSA10 (USA300) clones (94.1%; n = 4255), while the remaining case (n = 266) were CMRSA7 (USA400) clones. Period prevalence of CMRSA10 increased from 3.6 cases/100000 population in 2004, to 41.3 cases/100000 population in 2014. Geospatial analysis demonstrated wide dissemination of CMRSA10 annually in the city. Those who are English speaking (RR = 0.05, p < 0.0001), identify as visible minority Chinese (RR = 0.09, p = 0.0023) or visible minority South Asian (RR = 0.25, p = 0.015), and have a high median household income (RR = 0.27, p < 0.0001) have a significantly decreased relative risk of CMRSA10 infections. Conclusions CMRSA10 prevalence increased between 2004 and 2007, followed by a stabilization of cases by 2014. Certain sociodemographic factors were protective from CMRSA10 infections. The model of MRSA population-surveillance and geomap outbreak events can be used to track the epidemiology of MRSA in any jurisdiction.
- ItemOpen AccessSociodemographic associations with abnormal estimated glomerular filtration rate (eGFR) in a large Canadian city: a cross-sectional observation study(2018-08-09) Ma, Irene; Guo, Maggie; Muruve, Daniel; Benediktsson, Hallgrimur; Naugler, ChristopherAbstract Background Chronic kidney disease (CKD) is often asymptomatic in its early stages but is indicated and is diagnosed with an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73m2. Certain sociodemographic groups are known to be at risk for CKD, but it is unclear if there are strong associations between these at risk groups with abnormal eGFR test results in Canada. Using only secondary laboratory and Census data, geospatial variation and sociodemographic associations with abnormal eGFR result rate were investigated in Calgary, Alberta. Methods Secondary laboratory data from all adult community patients who received an eGFR test result were collected from Calgary Laboratory Service’s Laboratory Information System, which is the sole supplier of laboratory services for the large metropolitan city. Group-level sociodemographic variables were inferred by combining laboratory data with the 2011 Canadian Census data. Poisson regression and relative risk (RR) were used to calculate associations between sociodemographic variables with abnormal eGFR. Geographical distribution of abnormal eGFR result rates were analyzed by geospatial analysis using ArcGIS. Results Of the 346,663 adult community patients who received an eGFR test result, 28,091 were abnormal (8.1%; eGFR < 60 ml/min/1.73m2). Geospatial analysis revealed distinct geographical variation in abnormal eGFR result rates in Calgary. Women (RR = 1.11, P < 0.0001), and the elderly (age ≥ 70 years; P < 0.0001) were significantly associated with an increased risk for CKD, while visible minority Chinese (RR = 0.73, P = 0.0011), South Asians (RR = 0.67, P < 0.0001) and those with a high median household income (RR = 0.88, P < 0.0001) had a significantly reduced risk for CKD. Conclusions Presented here are significant sociodemographic risk associations, and geospatial clustering of abnormal eGFR result rates in a large metropolitan Canadian city. Using solely publically available secondary laboratory and Census data, the results from this study aligns with known sociodemographic risk factors for CKD, as certain sociodemographic variables were at a higher risk for having an abnormal eGFR test result, while others were protective in this analysis.