title: Heat-health warning systems: a comparison of the predictive capacity of different approaches to identifying dangerously hot days.
abstract: OBJECTIVE
  We compared the ability of several heat-health warning systems to predict days of heat-associated mortality using common data sets.
  
  
  METHODS
  Heat-health warning systems initiate emergency public health interventions once forecasts have identified weather conditions to breach predetermined trigger levels. We examined 4 commonly used trigger-setting approaches: (1) synoptic classification, (2) epidemiologic assessment of the temperature-mortality relationship, (3) temperature-humidity index, and (4) physiologic classification. We applied each approach in Chicago, Illinois; London, United Kingdom; Madrid, Spain; and Montreal, Canada, to identify days expected to be associated with the highest heat-related mortality.
  
  
  RESULTS
  We found little agreement across the approaches in which days were identified as most dangerous. In general, days identified by temperature-mortality assessment were associated with the highest excess mortality.
  
  
  CONCLUSIONS
  Triggering of alert days and ultimately the initiation of emergency responses by a heat-health warning system varies significantly across approaches adopted to establish triggers.
authors.affiliation: Public and Environmental Health Research Unit, London School of Hygiene and Tropical Medicine, Keppel St, London WC1E 7HT, UK. shakoor.hajat@lshtm.ac.uk
authors.forename: Shakoor
authors.initials: S
authors.lastname: Hajat
authors.forename: Scott C
authors.initials: SC
authors.lastname: Sheridan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Allen
authors.forename: Mathilde
authors.initials: M
authors.lastname: Pascal
authors.forename: Karine
authors.initials: K
authors.lastname: Laaidi
authors.forename: Abderrahmane
authors.initials: A
authors.lastname: Yagouti
authors.forename: Ugis
authors.initials: U
authors.lastname: Bickis
authors.forename: Aurelio
authors.initials: A
authors.lastname: Tobias
authors.forename: Denis
authors.initials: D
authors.lastname: Bourque
authors.forename: Ben G
authors.initials: BG
authors.lastname: Armstrong
authors.forename: Tom
authors.initials: T
authors.lastname: Kosatsky
mesh_terms: D002641:Chicago / Q000453:epidemiology; D005544:Forecasting; D018882:Heat Stress Disorders / Q000401:mortality / Q000517:prevention & control*; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D006813:Humidity; D008131:London / Q000453:epidemiology; D009026:Mortality; D011634:Public Health / Q000379:methods; D011792:Quebec / Q000453:epidemiology; D013030:Spain / Q000453:epidemiology
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