title: A proposed case-control framework to probabilistically classify individual deaths as expected or excess during extreme hot weather events.
abstract: Most excess deaths that occur during extreme hot weather events do not have natural heat recorded as an underlying or contributing cause. This study aims to identify the specific individuals who died because of hot weather using only secondary data. A novel approach was developed in which the expected number of deaths was repeatedly sampled from all deaths that occurred during a hot weather event, and compared with deaths during a control period. The deaths were compared with respect to five factors known to be associated with hot weather mortality. Individuals were ranked by their presence in significant models over 100 trials of 10,000 repetitions. Those with the highest rankings were identified as probable excess deaths. Sensitivity analyses were performed on a range of model combinations. These methods were applied to a 2009 hot weather event in greater Vancouver, Canada.
  
  
  
  The excess deaths identified were sensitive to differences in model combinations, particularly between univariate and multivariate approaches. One multivariate and one univariate combination were chosen as the best models for further analyses. The individuals identified by multiple combinations suggest that marginalized populations in greater Vancouver are at higher risk of death during hot weather.
  
  
  
  This study proposes novel methods for classifying specific deaths as expected or excess during a hot weather event. Further work is needed to evaluate performance of the methods in simulation studies and against clinically identified cases. If confirmed, these methods could be applied to a wide range of populations and events of interest.
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada. sarah.henderson@bccdc.ca.|School of Population and Public Health, The University of British Columbia, 2206 East Mall, 3rd Floor, Vancouver, BC, V6T 1Z3, Canada. sarah.henderson@bccdc.ca.
authors.forename: Sarah B
authors.initials: SB
authors.lastname: Henderson
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada.
authors.forename: Jillian S
authors.initials: JS
authors.lastname: Gauld
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Rauch
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada.
authors.forename: Kathleen E
authors.initials: KE
authors.lastname: McLean
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada.
authors.forename: Nikolas
authors.initials: N
authors.lastname: Krstic
authors.affiliation: Center for Policy Informatics, School of Public Affairs, Arizona State University, Phoenix, AZ, 85004, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Hondula
authors.affiliation: Environmental Health Services, British Columbia Centre for Disease Control, 655 West 12th Avenue, Vancouver, BC, V5Z 4R4, Canada.
authors.forename: Tom
authors.initials: T
authors.lastname: Kosatsky
mesh_terms: D000368:Aged; D001955:British Columbia / Q000453:epidemiology; D016022:Case-Control Studies; D055874:Extreme Heat / Q000009:adverse effects*; D006801:Humans; D008962:Models, Theoretical; D009026:Mortality
keywords: Administrative data; Case-control; Extreme hot weather; Population mortality; Public health; Vulnerability