International Journal of Public Health

, Volume 55, Issue 2, pp 133–137 | Cite as

A simple method for estimating excess mortality due to heat waves, as applied to the 2006 California heat wave

  • Sumi HoshikoEmail author
  • Paul English
  • Daniel Smith
  • Roger Trent
Brief Report



To characterize excess mortality during a major heat wave in California and its regions; to assess the validity of a simple method.


We calculated mortality rate ratios for the heat-wave period, using a reference period of the same number of days from the same summer. We conducted alternative analyses and compared our results with those from a time-series model.


We estimated 655 excess deaths, a 6% increase (95% confidence interval, 3–9%), impacting varied geographic/climate regions. Alternate analyses supported model validity.


California experienced excess heat-wave related mortality not restricted to high heat regions. As climate change is anticipated to increase heat events, public health efforts to monitor effects assume greater importance.


Climate change Global warming Heat wave Mortality Monitoring Surveillance 


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Copyright information

© Birkhäuser Verlag, Basel/Switzerland 2009

Authors and Affiliations

  • Sumi Hoshiko
    • 1
    Email author
  • Paul English
    • 1
  • Daniel Smith
    • 1
  • Roger Trent
    • 2
  1. 1.Environmental Health Investigations BranchCalifornia Department of Public HealthRichmondUSA
  2. 2.Epidemiology and Prevention for Injury Control BranchCalifornia Department of Public HealthSacramentoUSA

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