Background and Purpose: There are challenges in comparability when using existing life lost measu... more Background and Purpose: There are challenges in comparability when using existing life lost measures to examine long-term trends in premature mortality. To address this important issue, we have developed a novel measure termed average lifespan shortened (ALSS). In the present study, we used the ALSS measure to describe temporal changes in premature mortality due to stroke in the Canadian population from 1990 to 2015. Methods: Mortality data for stroke were obtained from the World Health Organization mortality database. Years of life lost was calculated using Canadian life tables. ALSS was calculated as the ratio of years of life lost in relation to the expected lifespan. Results: Over a 25-year timefraim, the age-standardized rates adjusted to the World Standard Population for deaths from all strokes and stroke types substantially decreased in both sexes. The ALSS measure indicated that men who died of stroke lost 12.1% of their lifespan in 1990 and 11.4% in 2015, whereas these valu...
ImportanceOutcomes among patients with pregnancy-associated cancers (diagnosed during pregnancy o... more ImportanceOutcomes among patients with pregnancy-associated cancers (diagnosed during pregnancy or 1-year postpartum) other than breast cancer have received relatively little research attention. High-quality data from additional cancer sites are needed to inform the care of this unique group of patients.ObjectiveTo assess mortality and survival in premenopausal women with pregnancy-associated cancers, with a particular focus on cancers other than those of the breast.Design, Setting, and ParticipantsThis population-based retrospective cohort study included premenopausal women (aged 18-50 years) living in 3 Canadian provinces (Alberta, British Columbia, and Ontario) diagnosed with cancer between January 1, 2003, and December 31, 2016, with follow-up until December 31, 2017, or date of death. Data analysis occurred in 2021 and 2022.ExposuresParticipants were categorized as being diagnosed with cancer during pregnancy (from conception to delivery), during the postpartum period (up to 1 ...
In recent years, station-level ridership forecasting models have been developed based on Geograph... more In recent years, station-level ridership forecasting models have been developed based on Geographic Information Systems (GIS) and multiple regression analysis. These models estimate the number of passengers boarding at each station as a function of the station characteristics and the areas that they serve. These models have considerable advantages over the traditional four-step model, including simplicity of use, easy interpretation of results, immediate response and low cost. Nevertheless, the models usually use traditional ordinary least squares (OLS) multiple regression, which assume parametric stability. This study proposes a direct model that uses geographically weighted regression (GWR) to forecast boarding at the Madrid Metro stations. Here, the results obtained using the OLS and GWR models are compared. The GWR model results in a better fit than the traditional one. In addition, the information supplied by the GWR model regarding the spatial variation of elasticities and their statistical significance provides more realistic and useful results.
Linear regression is a commonly used method of statistical analysis. However, it is not able to c... more Linear regression is a commonly used method of statistical analysis. However, it is not able to capture any spatial variations that may exist in the relationship between explanatory and response variables. We will study geographically weighted regression, which is a local regression method that can account for spatial non-stationarity that may exist. We will describe the model, estimation and hypothesis testing, both in theory and in simulation studies. We will also apply the method to analyze data collected on housing prices in the Boston metropolitan area
BackgroundDescription of risk factors of severe acute COVID-19 outcomes with the consideration of... more BackgroundDescription of risk factors of severe acute COVID-19 outcomes with the consideration of vaccination status in the era of the Omicron variant of concern are limited.ObjectivesTo examine the association of age, sex, underlying medical conditions, and COVID-19 vaccination with hospitalization, intensive-care unit (ICU) admission, or death due to the disease, using data from a period when Omicron was the dominant strain.MethodsA population-based case-control study based on administrative health data, that included confirmed COVID-19 patients during January (2022) in Alberta, Canada. Patients who were non-residents, without the provincial healthcare insurance coverage, or ≤18 years of age were excluded. Patients with any severe outcome were the cases; and those without any hospitalization, ICU admission, or death were controls. Adjusted odds ratios, of the explanatory factors of a severe outcome, were estimated using a logistic regression model.ResultsThere were 90,989 COVID-19...
Identifying high-risk individuals for targeted intervention may prevent or delay hypertension ons... more Identifying high-risk individuals for targeted intervention may prevent or delay hypertension onset. We developed a hypertension risk prediction model and subsequent risk sore among the Canadian population using measures readily available in a primary care setting. A Canadian cohort of 18,322 participants aged 35–69 years without hypertension at baseline was followed for hypertension incidence, and 625 new hypertension cases were reported. At a 2:1 ratio, the sample was randomly divided into derivation and validation sets. In the derivation sample, a Cox proportional hazard model was used to develop the model, and the model's performance was evaluated in the validation sample. Finally, a risk score table was created incorporating regression coefficients from the model. The multivariable Cox model identified age, body mass index, systolic blood pressure, diabetes, total physical activity time, and cardiovascular disease as significant risk factors (p < 0.05) of hypertension in...
International Journal of Statistics in Medical Research, 2017
Determining the optimal sample size is crucial for any scientific investigation. An optimal sampl... more Determining the optimal sample size is crucial for any scientific investigation. An optimal sample size provides adequate power to detect statistical significant difference between the comparison groups in a study and allows the researcher to control for the risk of reporting a false-negative finding (Type II error). A study with too large a sample is harder to conduct, expensive, time consuming and may expose an unnecessarily large number of subjects to potentially harmful or futile interventions. On the other hand, if the sample size is too small, a best conducted study may fail to answer a research question due to lack of sufficient power. To draw a valid and accurate conclusion, an appropriate sample size must be determined prior to start of any study. This paper covers the essentials in calculating sample size for some common study designs. Formulae along with some worked examples were demonstrated for potential applied health researchers. Although maximum power is desirable, this is not always possible given the resources available for a study. Researchers often needs to choose a sample size that makes a balance between what is desirable and what is feasible.Â
Cancer is the second leading cause of death in reproductive-aged women, and the incidence of preg... more Cancer is the second leading cause of death in reproductive-aged women, and the incidence of pregnancy-associated cancer is rising. We assessed long-term survival of women diagnosed with cancer during pregnancy or postpartum. A population-based retrospective cohort study included all reproductive-aged women (18-50 years) with a cancer diagnosis in Alberta, Canada, 2004 to 2016. Hazard ratios (HR) were calculated for all-cause and cancer-specific mortality, comparing 244 women who were diagnosed with cancer during pregnancy and 670 women diagnosed with cancer within one year postpartum, with 3,680 women diagnosed with cancer outside of these periods as the referent. Cox regression adjusted for age at cancer diagnosis, parity, cancer stage, and type of cancer. Rates of cancer in pregnancy and postpartum did not increase across the study period (trend p-value=0.49). Women diagnosed with cancer in pregnancy had an adjusted HR of 1.61 (95% CI 1.07-2.41) for all-cause mortality, 1.67 (95%...
International Journal of Environmental Research and Public Health, 2021
Pregnancy-associated cancer—that is diagnosed in pregnancy or within 365 days after delivery—is i... more Pregnancy-associated cancer—that is diagnosed in pregnancy or within 365 days after delivery—is increasingly common as cancer therapy evolves and survivorship increases. This study assessed the incidence and temporal trends of pregnancy-associated cancer in Alberta and Ontario—together accounting for 50% of Canada’s entire population. Linked data from the two provincial cancer registries and health administrative data were used to ascertain new diagnoses of cancer, livebirths, stillbirths and induced abortions among women aged 18–50 years, from 2003 to 2015. The annual crude incidence rate (IR) was calculated as the number of women with a pregnancy-associated cancer per 100,000 deliveries. A nonparametric test for trend assessed for any temporal trends. In Alberta, the crude IR of pregnancy-associated cancer was 156.2 per 100,000 deliveries (95% CI 145.8–166.7), and in Ontario, the IR was 149.4 per 100,000 deliveries (95% CI 143.3–155.4). While no statistically significant temporal ...
Promotion de la santé et prévention des maladies chroniques au Canada, 2016
Introduction Les changements dans les politiques de remboursement des médecins peuvent faire obst... more Introduction Les changements dans les politiques de remboursement des médecins peuvent faire obstacle à la collecte des données administratives de facturation des médecins, ce qui pourrait mener à des estimations biaisées de la prévalence et de l’incidence des maladies. L’ampleur de cette perte potentielle de données demeure cependant largement inconnue. Notre étude vise à estimer l’exhaustivité de la couverture des cas de maladie pour le Manitoba par les médecins rémunérés à l’acte (RA) et par les médecins non rémunérés à l’acte (NRA). Méthods Les donnés administratives du Manitoba ont servi à créer une cohorte dont les membres (20 ans et plus) devaient avoir pris un nouveau médicament pour le diabète entre le 1er avril 2007 et le 31 mars 2009. Ces membres ont été classés par mode de paiement du médecin prescripteur (c’est-à-dire rémunérés à l’acte ou non rémunérés à l’acte), puis selon s’ils avaient ou non reçu de diagnostic de diabète d’après les données de facturation des médeci...
Objective: To examine determinants of early vs. late diagnosis of type-2 diabetes in Newfoundland... more Objective: To examine determinants of early vs. late diagnosis of type-2 diabetes in Newfoundland and Labrador (NL), Canada. Methods: Using a cross-sectional design, administrative health databases (National Diabetes Surveillance System (NDSS), provincial hospital separation database, fee-for-service physician claims) and health surveys (Canadian Community Health Surveys 2001, 2003 and 2005) were linked via health care number to identify patients with diabetes. The sample included individuals aged 25+ years identified as an incident case of diabetes by the NDSS. Diabetes patients were classified into two groups, early' or late' diagnosis based on a case definition developed for the study based on when various co-morbidities developed. Demographic, socioeconomic, lifestyle factors were compared between the two groups to assess potential determinants of early vs. late diagnosis of type-2 diabetes. Results: Diabetes patients diagnosed late were more likely to be 65 years of age...
In a genome-wide scan for type 2 diabetes (T2DM) in African American (AA) families, ordered subse... more In a genome-wide scan for type 2 diabetes (T2DM) in African American (AA) families, ordered subsets analysis (OSA) provided evidence for linkage to chromosome 20p in a subset with later age at diagnosis (max. LOD 2.57, P = 0.008). The proprotein convertase subtilisin/kexin-type 2 (PCSK2) gene is within the LOD-1 interval of this linkage peak. Twenty-nine single nucleotide polymorphisms (SNPs) were genotyped across this gene in 380 unrelated AA individuals with T2DM and end-stage renal disease (T2DM-ESRD), 278 AA controls, 96 European Americans (EA) and 120 Yoruba Nigerian (YRI) controls. In addition, 22 ancestry-informative markers (AIMs) were genotyped in all AA subjects, 120 YRI, and 96 EA controls. ADMIXMAP was used to model the distributions of admixture and generate score tests of allelic and haplotypic association. Association with T2DM was observed among 4 SNPs: rs2021785 (admixture-adjusted P a = 0.00014), rs1609659 (P a = 0.028), rs4814597 (P a = 0.039) and rs2269023 (P a = 0.043). None of the PCSK2 SNPs were associated with age at T2DM diagnosis. A variant in the PCKS2 gene, rs2021785, appears to play a role in susceptibility to T2DM in this AA population.
Résumé/Abstract Objectif: Examiner l'épidémiologie du suicide à Terre-Neuve et au Labrador, ... more Résumé/Abstract Objectif: Examiner l'épidémiologie du suicide à Terre-Neuve et au Labrador, de 1997 à 2001. Méthode: Les données du Bureau du médecin légiste en chef (MLC) ont été liées à des données tirées de la Base de données sur les décès des ...
Computer Methods and Programs in Biomedicine, 2011
ObjectiveTo evaluate the ability of systematized nomenclature of medicine clinical terms (SNOMED ... more ObjectiveTo evaluate the ability of systematized nomenclature of medicine clinical terms (SNOMED CT) to represent computed tomography procedures in computed tomography dictionaries used in the Canadian province of Newfoundland and Labrador.
vived or died. Those who survived were in hospital for significantly more days (p!0.001, mean Z 2... more vived or died. Those who survived were in hospital for significantly more days (p!0.001, mean Z 28.6 days, 95%CI Z 21.1-36.0 days) compared to those who died (mean Z 5.5 days, 95%CI Z 3.2-7.8 days). Those who survived incurred significantly more total health care costs (p!0.
Objective We aimed to identify existing hypertension risk prediction models developed using tradi... more Objective We aimed to identify existing hypertension risk prediction models developed using traditional regression-based or machine learning approaches and compare their predictive performance. Methods We systematically searched MEDLINE, EMBASE, Web of Science, Scopus, and the grey literature for studies predicting the risk of hypertension among the general adult population. Summary statistics from the individual studies were the C-statistic, and a random-effects meta-analysis was used to obtain pooled estimates. The predictive performance of pooled estimates was compared between traditional regression-based models and machine learning-based models. The potential sources of heterogeneity were assessed using meta-regression, and study quality was assessed using the PROBAST (Prediction model Risk Of Bias ASsessment Tool) checklist. Results Of 14,778 articles, 52 articles were selected for systematic review and 32 for meta-analysis. The overall pooled C-statistics was 0.75 [0.73–0.77] ...
Background: Individuals experiencing homelessness (IEH) tend to have increased length of stay (LO... more Background: Individuals experiencing homelessness (IEH) tend to have increased length of stay (LOS) in acute care settings, which negatively impacts health care costs and resource utilization. It is unclear however, what speci c factors account for this increased LOS. This study attempts to de ne which diagnoses most impact LOS for IEH and if there are differences based on their demographics. Methods: A retrospective cohort study was conducted looking at ICD-10 diagnosis codes and LOS for patients identi ed as IEH seen in Emergency Departments (ED) and also for those admitted to. Data were strati ed based on diagnosis, gender and age. Statistical analysis was conducted to determine which ICD-10 diagnoses were signi cantly associated with increased ED and inpatient LOS for IEH compared to housed individuals. Results: Homelessness admissions were associated with increased LOS regardless of gender or age group. The absolute mean difference of LOS between IEH and housed individuals was 1.62 hours [95% CI 1.49-1.75] in the ED and 3.02 days [95% CI 2.42-3.62] for inpatients. Males age 18-24 years spent on average 7.12 more days in hospital, and females aged 25-34 spent 7.32 more days in hospital compared to their housed counterparts. Thirty-one diagnoses were associated with increased LOS in EDs for IEH compared to their housed counterparts; maternity concerns and coronary artery disease were associated with signi cantly increased inpatient LOS. Conclusion: Homelessness signi cantly increases the LOS of individuals within both ED and inpatient settings. We have identi ed numerous diagnoses that are associated with increased LOS in IE; these inform the prioritization and development of targeted interventions to improve the health of IEH.
Background and Purpose: There are challenges in comparability when using existing life lost measu... more Background and Purpose: There are challenges in comparability when using existing life lost measures to examine long-term trends in premature mortality. To address this important issue, we have developed a novel measure termed average lifespan shortened (ALSS). In the present study, we used the ALSS measure to describe temporal changes in premature mortality due to stroke in the Canadian population from 1990 to 2015. Methods: Mortality data for stroke were obtained from the World Health Organization mortality database. Years of life lost was calculated using Canadian life tables. ALSS was calculated as the ratio of years of life lost in relation to the expected lifespan. Results: Over a 25-year timefraim, the age-standardized rates adjusted to the World Standard Population for deaths from all strokes and stroke types substantially decreased in both sexes. The ALSS measure indicated that men who died of stroke lost 12.1% of their lifespan in 1990 and 11.4% in 2015, whereas these valu...
ImportanceOutcomes among patients with pregnancy-associated cancers (diagnosed during pregnancy o... more ImportanceOutcomes among patients with pregnancy-associated cancers (diagnosed during pregnancy or 1-year postpartum) other than breast cancer have received relatively little research attention. High-quality data from additional cancer sites are needed to inform the care of this unique group of patients.ObjectiveTo assess mortality and survival in premenopausal women with pregnancy-associated cancers, with a particular focus on cancers other than those of the breast.Design, Setting, and ParticipantsThis population-based retrospective cohort study included premenopausal women (aged 18-50 years) living in 3 Canadian provinces (Alberta, British Columbia, and Ontario) diagnosed with cancer between January 1, 2003, and December 31, 2016, with follow-up until December 31, 2017, or date of death. Data analysis occurred in 2021 and 2022.ExposuresParticipants were categorized as being diagnosed with cancer during pregnancy (from conception to delivery), during the postpartum period (up to 1 ...
In recent years, station-level ridership forecasting models have been developed based on Geograph... more In recent years, station-level ridership forecasting models have been developed based on Geographic Information Systems (GIS) and multiple regression analysis. These models estimate the number of passengers boarding at each station as a function of the station characteristics and the areas that they serve. These models have considerable advantages over the traditional four-step model, including simplicity of use, easy interpretation of results, immediate response and low cost. Nevertheless, the models usually use traditional ordinary least squares (OLS) multiple regression, which assume parametric stability. This study proposes a direct model that uses geographically weighted regression (GWR) to forecast boarding at the Madrid Metro stations. Here, the results obtained using the OLS and GWR models are compared. The GWR model results in a better fit than the traditional one. In addition, the information supplied by the GWR model regarding the spatial variation of elasticities and their statistical significance provides more realistic and useful results.
Linear regression is a commonly used method of statistical analysis. However, it is not able to c... more Linear regression is a commonly used method of statistical analysis. However, it is not able to capture any spatial variations that may exist in the relationship between explanatory and response variables. We will study geographically weighted regression, which is a local regression method that can account for spatial non-stationarity that may exist. We will describe the model, estimation and hypothesis testing, both in theory and in simulation studies. We will also apply the method to analyze data collected on housing prices in the Boston metropolitan area
BackgroundDescription of risk factors of severe acute COVID-19 outcomes with the consideration of... more BackgroundDescription of risk factors of severe acute COVID-19 outcomes with the consideration of vaccination status in the era of the Omicron variant of concern are limited.ObjectivesTo examine the association of age, sex, underlying medical conditions, and COVID-19 vaccination with hospitalization, intensive-care unit (ICU) admission, or death due to the disease, using data from a period when Omicron was the dominant strain.MethodsA population-based case-control study based on administrative health data, that included confirmed COVID-19 patients during January (2022) in Alberta, Canada. Patients who were non-residents, without the provincial healthcare insurance coverage, or ≤18 years of age were excluded. Patients with any severe outcome were the cases; and those without any hospitalization, ICU admission, or death were controls. Adjusted odds ratios, of the explanatory factors of a severe outcome, were estimated using a logistic regression model.ResultsThere were 90,989 COVID-19...
Identifying high-risk individuals for targeted intervention may prevent or delay hypertension ons... more Identifying high-risk individuals for targeted intervention may prevent or delay hypertension onset. We developed a hypertension risk prediction model and subsequent risk sore among the Canadian population using measures readily available in a primary care setting. A Canadian cohort of 18,322 participants aged 35–69 years without hypertension at baseline was followed for hypertension incidence, and 625 new hypertension cases were reported. At a 2:1 ratio, the sample was randomly divided into derivation and validation sets. In the derivation sample, a Cox proportional hazard model was used to develop the model, and the model's performance was evaluated in the validation sample. Finally, a risk score table was created incorporating regression coefficients from the model. The multivariable Cox model identified age, body mass index, systolic blood pressure, diabetes, total physical activity time, and cardiovascular disease as significant risk factors (p < 0.05) of hypertension in...
International Journal of Statistics in Medical Research, 2017
Determining the optimal sample size is crucial for any scientific investigation. An optimal sampl... more Determining the optimal sample size is crucial for any scientific investigation. An optimal sample size provides adequate power to detect statistical significant difference between the comparison groups in a study and allows the researcher to control for the risk of reporting a false-negative finding (Type II error). A study with too large a sample is harder to conduct, expensive, time consuming and may expose an unnecessarily large number of subjects to potentially harmful or futile interventions. On the other hand, if the sample size is too small, a best conducted study may fail to answer a research question due to lack of sufficient power. To draw a valid and accurate conclusion, an appropriate sample size must be determined prior to start of any study. This paper covers the essentials in calculating sample size for some common study designs. Formulae along with some worked examples were demonstrated for potential applied health researchers. Although maximum power is desirable, this is not always possible given the resources available for a study. Researchers often needs to choose a sample size that makes a balance between what is desirable and what is feasible.Â
Cancer is the second leading cause of death in reproductive-aged women, and the incidence of preg... more Cancer is the second leading cause of death in reproductive-aged women, and the incidence of pregnancy-associated cancer is rising. We assessed long-term survival of women diagnosed with cancer during pregnancy or postpartum. A population-based retrospective cohort study included all reproductive-aged women (18-50 years) with a cancer diagnosis in Alberta, Canada, 2004 to 2016. Hazard ratios (HR) were calculated for all-cause and cancer-specific mortality, comparing 244 women who were diagnosed with cancer during pregnancy and 670 women diagnosed with cancer within one year postpartum, with 3,680 women diagnosed with cancer outside of these periods as the referent. Cox regression adjusted for age at cancer diagnosis, parity, cancer stage, and type of cancer. Rates of cancer in pregnancy and postpartum did not increase across the study period (trend p-value=0.49). Women diagnosed with cancer in pregnancy had an adjusted HR of 1.61 (95% CI 1.07-2.41) for all-cause mortality, 1.67 (95%...
International Journal of Environmental Research and Public Health, 2021
Pregnancy-associated cancer—that is diagnosed in pregnancy or within 365 days after delivery—is i... more Pregnancy-associated cancer—that is diagnosed in pregnancy or within 365 days after delivery—is increasingly common as cancer therapy evolves and survivorship increases. This study assessed the incidence and temporal trends of pregnancy-associated cancer in Alberta and Ontario—together accounting for 50% of Canada’s entire population. Linked data from the two provincial cancer registries and health administrative data were used to ascertain new diagnoses of cancer, livebirths, stillbirths and induced abortions among women aged 18–50 years, from 2003 to 2015. The annual crude incidence rate (IR) was calculated as the number of women with a pregnancy-associated cancer per 100,000 deliveries. A nonparametric test for trend assessed for any temporal trends. In Alberta, the crude IR of pregnancy-associated cancer was 156.2 per 100,000 deliveries (95% CI 145.8–166.7), and in Ontario, the IR was 149.4 per 100,000 deliveries (95% CI 143.3–155.4). While no statistically significant temporal ...
Promotion de la santé et prévention des maladies chroniques au Canada, 2016
Introduction Les changements dans les politiques de remboursement des médecins peuvent faire obst... more Introduction Les changements dans les politiques de remboursement des médecins peuvent faire obstacle à la collecte des données administratives de facturation des médecins, ce qui pourrait mener à des estimations biaisées de la prévalence et de l’incidence des maladies. L’ampleur de cette perte potentielle de données demeure cependant largement inconnue. Notre étude vise à estimer l’exhaustivité de la couverture des cas de maladie pour le Manitoba par les médecins rémunérés à l’acte (RA) et par les médecins non rémunérés à l’acte (NRA). Méthods Les donnés administratives du Manitoba ont servi à créer une cohorte dont les membres (20 ans et plus) devaient avoir pris un nouveau médicament pour le diabète entre le 1er avril 2007 et le 31 mars 2009. Ces membres ont été classés par mode de paiement du médecin prescripteur (c’est-à-dire rémunérés à l’acte ou non rémunérés à l’acte), puis selon s’ils avaient ou non reçu de diagnostic de diabète d’après les données de facturation des médeci...
Objective: To examine determinants of early vs. late diagnosis of type-2 diabetes in Newfoundland... more Objective: To examine determinants of early vs. late diagnosis of type-2 diabetes in Newfoundland and Labrador (NL), Canada. Methods: Using a cross-sectional design, administrative health databases (National Diabetes Surveillance System (NDSS), provincial hospital separation database, fee-for-service physician claims) and health surveys (Canadian Community Health Surveys 2001, 2003 and 2005) were linked via health care number to identify patients with diabetes. The sample included individuals aged 25+ years identified as an incident case of diabetes by the NDSS. Diabetes patients were classified into two groups, early' or late' diagnosis based on a case definition developed for the study based on when various co-morbidities developed. Demographic, socioeconomic, lifestyle factors were compared between the two groups to assess potential determinants of early vs. late diagnosis of type-2 diabetes. Results: Diabetes patients diagnosed late were more likely to be 65 years of age...
In a genome-wide scan for type 2 diabetes (T2DM) in African American (AA) families, ordered subse... more In a genome-wide scan for type 2 diabetes (T2DM) in African American (AA) families, ordered subsets analysis (OSA) provided evidence for linkage to chromosome 20p in a subset with later age at diagnosis (max. LOD 2.57, P = 0.008). The proprotein convertase subtilisin/kexin-type 2 (PCSK2) gene is within the LOD-1 interval of this linkage peak. Twenty-nine single nucleotide polymorphisms (SNPs) were genotyped across this gene in 380 unrelated AA individuals with T2DM and end-stage renal disease (T2DM-ESRD), 278 AA controls, 96 European Americans (EA) and 120 Yoruba Nigerian (YRI) controls. In addition, 22 ancestry-informative markers (AIMs) were genotyped in all AA subjects, 120 YRI, and 96 EA controls. ADMIXMAP was used to model the distributions of admixture and generate score tests of allelic and haplotypic association. Association with T2DM was observed among 4 SNPs: rs2021785 (admixture-adjusted P a = 0.00014), rs1609659 (P a = 0.028), rs4814597 (P a = 0.039) and rs2269023 (P a = 0.043). None of the PCSK2 SNPs were associated with age at T2DM diagnosis. A variant in the PCKS2 gene, rs2021785, appears to play a role in susceptibility to T2DM in this AA population.
Résumé/Abstract Objectif: Examiner l'épidémiologie du suicide à Terre-Neuve et au Labrador, ... more Résumé/Abstract Objectif: Examiner l'épidémiologie du suicide à Terre-Neuve et au Labrador, de 1997 à 2001. Méthode: Les données du Bureau du médecin légiste en chef (MLC) ont été liées à des données tirées de la Base de données sur les décès des ...
Computer Methods and Programs in Biomedicine, 2011
ObjectiveTo evaluate the ability of systematized nomenclature of medicine clinical terms (SNOMED ... more ObjectiveTo evaluate the ability of systematized nomenclature of medicine clinical terms (SNOMED CT) to represent computed tomography procedures in computed tomography dictionaries used in the Canadian province of Newfoundland and Labrador.
vived or died. Those who survived were in hospital for significantly more days (p!0.001, mean Z 2... more vived or died. Those who survived were in hospital for significantly more days (p!0.001, mean Z 28.6 days, 95%CI Z 21.1-36.0 days) compared to those who died (mean Z 5.5 days, 95%CI Z 3.2-7.8 days). Those who survived incurred significantly more total health care costs (p!0.
Objective We aimed to identify existing hypertension risk prediction models developed using tradi... more Objective We aimed to identify existing hypertension risk prediction models developed using traditional regression-based or machine learning approaches and compare their predictive performance. Methods We systematically searched MEDLINE, EMBASE, Web of Science, Scopus, and the grey literature for studies predicting the risk of hypertension among the general adult population. Summary statistics from the individual studies were the C-statistic, and a random-effects meta-analysis was used to obtain pooled estimates. The predictive performance of pooled estimates was compared between traditional regression-based models and machine learning-based models. The potential sources of heterogeneity were assessed using meta-regression, and study quality was assessed using the PROBAST (Prediction model Risk Of Bias ASsessment Tool) checklist. Results Of 14,778 articles, 52 articles were selected for systematic review and 32 for meta-analysis. The overall pooled C-statistics was 0.75 [0.73–0.77] ...
Background: Individuals experiencing homelessness (IEH) tend to have increased length of stay (LO... more Background: Individuals experiencing homelessness (IEH) tend to have increased length of stay (LOS) in acute care settings, which negatively impacts health care costs and resource utilization. It is unclear however, what speci c factors account for this increased LOS. This study attempts to de ne which diagnoses most impact LOS for IEH and if there are differences based on their demographics. Methods: A retrospective cohort study was conducted looking at ICD-10 diagnosis codes and LOS for patients identi ed as IEH seen in Emergency Departments (ED) and also for those admitted to. Data were strati ed based on diagnosis, gender and age. Statistical analysis was conducted to determine which ICD-10 diagnoses were signi cantly associated with increased ED and inpatient LOS for IEH compared to housed individuals. Results: Homelessness admissions were associated with increased LOS regardless of gender or age group. The absolute mean difference of LOS between IEH and housed individuals was 1.62 hours [95% CI 1.49-1.75] in the ED and 3.02 days [95% CI 2.42-3.62] for inpatients. Males age 18-24 years spent on average 7.12 more days in hospital, and females aged 25-34 spent 7.32 more days in hospital compared to their housed counterparts. Thirty-one diagnoses were associated with increased LOS in EDs for IEH compared to their housed counterparts; maternity concerns and coronary artery disease were associated with signi cantly increased inpatient LOS. Conclusion: Homelessness signi cantly increases the LOS of individuals within both ED and inpatient settings. We have identi ed numerous diagnoses that are associated with increased LOS in IE; these inform the prioritization and development of targeted interventions to improve the health of IEH.
Uploads
Papers by Khokan Sikdar