Jonathan Simkin

Mr. Jonathan Simkin

BC Cancer Research Center
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 February 2022 in Current Oncology
Verified
Journal Article
Open access
PDF file
HCHannah Caird
Hannah Caird
JSJonathan Simkin
Jonathan Simkin
LSLaurie Smith
Laurie Smith
DNDirk Van Niekerk
Dirk Van Niekerk
GOGina Ogilvie
Gina Ogilvie
Cervical cancer remains a common cancer affecting women in Canada. While cervical cancer incidence and mortality in Canada have declined for several decades due to the success of organized, provincial cervical cancer screening programs, further decreases will require enhancement of primary, secondary, and tertiary prevention efforts. The present commentary provides a historical overview of cervical cancer trends in Canada, presents current statistics on cervical cancer incidence, mortality and survival, and discusses future directions in relation to cervical cancer elimination.

23 October 2018 in Canadian Journal of Public Health
Verified
Journal Article
Closed access
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JSJonathan Simkin
Jonathan Simkin
GOGina Ogilvie
Gina Ogilvie
BHBrendan Hanley
Brendan Hanley
CECatherine Elliott
Catherine Elliott

22 April 2021 in CMAJ Open
Verified
Journal Article
Open access
PDF file
JSJonathan Simkin
Jonathan Simkin
LSLaurie Smith
Laurie Smith
DNDirk van Niekerk
Dirk van Niekerk
HCHannah Caird
Hannah Caird
TDTania Dearden
Tania Dearden
GOGina Ogilvie
Gina Ogilvie
Background: Although cancer screening has led to reductions in the incidence of invasive cervical cancer (ICC) across Canada, benefits of prevention efforts are not equitably distributed. This study investigated the sociodemographic characteristics of women with ICC in British Columbia compared with the general female population in the province. Methods: In this descriptive study, data of individuals 18 years and older diagnosed with ICC between 2004 and 2013 were obtained from the BC Cancer Registry. Self-reported sociodemographic characteristics were derived from standardized health assessment forms (HAFs) completed upon admission in the BC Cancer Registry. Standardized ratios (SRs) were derived by dividing observed and age-adjusted expected counts by ethnicity or race, language, and marital, smoking and urban–rural status. Differences between observed and expected counts were tested using χ2 goodness-of-fit tests. General population data were derived from the 2006 Census, 2011 National Household Survey and 2011/12 Canadian Community Health Survey. Results: Of 1705 total cases of ICC, 1315 were referred to BC Cancer (77.1%). Of those who were referred, 1215 (92.4%) completed HAFs. Among Indigenous women, more cases were observed (n = 85) than expected (n = 39; SR 2.16, 95% confidence interval [CI] 2.15–2.18). Among visible minorities, observed cases (n = 320) were higher than expected (n = 253; 95% CI 1.26–1.26). Elevated SRs were observed among women who self-identified as Korean (SR 1.78, 95% CI 1.76–1.80), Japanese (SR 1.77, 95% CI 1.74–1.79) and Filipino (SR 1.60, 95% CI 1.58–1.62); lower SRs were observed among South Asian women (SR 0.63, 95% CI 0.62–0.63). Elevated SRs were observed among current smokers (SR 1.34, 95% CI 1.33–1.34) and women living in rural-hub (SR 1.29, 95% CI 1.28–1.31) and rural or remote (SR 2.62, 95% CI 2.61–2.64) areas; the SR was lower among married women (SR 0.90, 95% CI 0.90–0.90). Interpretation: Women who self-identified as visible minorities, Indigenous, current smokers, nonmarried and from rural areas were overrepresented among women with ICC. Efforts are needed to address inequities to ensure all women benefit from cervical cancer prevention.

19 October 2022 in Frontiers in Oncology
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Journal Article
Open access
JSJonathan Simkin
Jonathan Simkin
TDTrevor J. B. Dummer
Trevor J. B. Dummer
AEAnders C. Erickson
Anders C. Erickson
MOMichael C. Otterstatter
Michael C. Otterstatter
RWRyan R. Woods
Ryan R. Woods
GOGina Ogilvie
Gina Ogilvie
Introduction: There is an increasing interest in small area analyses in cancer surveillance; however, technical capacity is limited and accessible analytical approaches remain to be determined. This study demonstrates an accessible approach for small area cancer risk estimation using Bayesian hierarchical models and data visualization through the smallareamapp R package.Materials and methods: Incident lung (N = 26,448), female breast (N = 28,466), cervical (N = 1,478), and colorectal (N = 25,457) cancers diagnosed among British Columbia (BC) residents between 2011 and 2018 were obtained from the BC Cancer Registry. Indirect age-standardization was used to derive age-adjusted expected counts and standardized incidence ratios (SIRs) relative to provincial rates. Moran’s I was used to assess the strength and direction of spatial autocorrelation. A modified Besag, York and Mollie model (BYM2) was used for model incidence counts to calculate posterior median relative risks (RR) by Community Health Service Areas (CHSA; N = 218), adjusting for spatial dependencies. Integrated Nested Laplace Approximation (INLA) was used for Bayesian model implementation. Areas with exceedance probabilities (above a threshold RR = 1.1) greater or equal to 80% were considered to have an elevated risk. The posterior median and 95% credible intervals (CrI) for the spatially structured effect were reported. Predictive posterior checks were conducted through predictive integral transformation values and observed versus fitted values.Results: The proportion of variance in the RR explained by a spatial effect ranged from 4.4% (male colorectal) to 19.2% (female breast). Lung cancer showed the greatest number of CHSAs with elevated risk (Nwomen = 50/218, Nmen = 44/218), representing 2357 total excess cases. The largest lung cancer RRs were 1.67 (95% CrI = 1.06–2.50; exceedance probability = 96%; cases = 13) among women and 2.49 (95% CrI = 2.14–2.88; exceedance probability = 100%; cases = 174) among men. Areas with small population sizes and extreme SIRs were generally smoothed towards the null (RR = 1.0).Discussion: We present a ready-to-use approach for small area cancer risk estimation and disease mapping using BYM2 and exceedance probabilities. We developed the smallareamapp R package, which provides a user-friendly interface through an R-Shiny application, for epidemiologists and surveillance experts to examine geographic variation in risk. These methods and tools can be used to estimate risk, generate hypotheses, and examine ecologic associations while adjusting for spatial dependency.

1 January 2017 in International Journal of Circumpolar Health
Verified
Journal Article
Open access
JSJonathan Simkin
Jonathan Simkin
RWRyan Woods
Ryan Woods
CECatherine Elliott
Catherine Elliott
Background: Although cancer is the leading cause of death in Canada, cancer in the North has been incompletely described. Objective: To determine cancer mortality rates in the Yukon Territory, compare them with Canadian rates, and identify major causes of cancer mortality. Design: The Yukon Vital Statistics Registry provided all cancer deaths for Yukon residents between 1999-2013. Age-standardised mortality rates (ASMRs) were calculated using direct standardisation and compared with Canadian rates. Standardised mortality ratios (SMRs) were calculated using indirect standardisation relative to age-specific rates from Canada, British Columbia (BC), and three sub-provincial BC administrative health regions : Interior Health (IH), Northern Health (NH) and Vancouver Coastal Health (VCH). Trends in smoothed ASMRs were examined with graphical methods. Results: Yukon’s all-cancer ASMRs were elevated compared with national and provincial rates for the entire period. Disparities were greatest compared with the urban VCH: prostate (SMRVCH=246.3, 95% CI 140.9–351.6), female lung (SMRVCH=221.2, 95% CI 154.3–288.1), female breast (SMRVCH=169.0 95% CI, 101.4–236.7), and total colorectal (SMRVCH=149.3, 95% CI 101.8–196.8) cancers were significantly elevated. Total stomach cancer mortality was significantly elevated compared with all comparators. Conclusions: Yukon cancer mortality rates were elevated compared with national, provincial, urban, and southern-rural jurisdictions. More research is required to elucidate these differences.

31 August 2023 in Current Oncology
Verified
Journal Article
Open access
PDF file
JSJonathan Simkin
Jonathan Simkin
EKEdwin Khoo
Edwin Khoo
MDMaryam Darvishian
Maryam Darvishian
JSJanette Sam
Janette Sam
PBParveen Bhatti
Parveen Bhatti
RWRyan R. Woods
Ryan R. Woods
Background: The successful implementation of an equitable lung cancer screening program requires consideration of factors that influence accessibility to screening services. Methods: Using lung cancer cases in British Columbia (BC), Canada, as a proxy for a screen-eligible population, spatial access to 36 screening sites was examined using geospatial mapping and vehicle travel time from residential postal code at diagnosis to the nearest site. The impact of urbanization and Statistics Canada’s Canadian Index of Multiple Deprivation were examined. Results: Median travel time to the nearest screening site was 11.7 min (interquartile range 6.2–23.2 min). Urbanization was significantly associated with shorter drive time (p < 0.001). Ninety-nine percent of patients with ≥60 min drive times lived in rural areas. Drive times were associated with sex, ethnocultural composition, situational vulnerability, economic dependency, and residential instability. For example, the percentage of cases with drive times ≥60 min among the least deprived situational vulnerability group was 4.7% versus 44.4% in the most deprived group. Conclusions: Populations at risk in rural and remote regions may face more challenges accessing screening services due to increased travel times. Drive times increased with increasing sociodemographic and economic deprivations highlighting groups that may require support to ensure equitable access to lung cancer screening.