| Orru et al. (1997-2013) | Northeastern Europe (Estonia) | Maximum temperatures | Seasonality and longer term trends | Deaths from external causes (ICD10 diagnosis codes V00 - Y99) | Poisson regression, combined with a distributed lag non-linear model | External cause mortality significantly increased on hot (the same and previous day) and cold days (a lag of 1 - 3 days) |
| Joe et al. (18-day period between 15 July and 1 August, 2006) | California | Heat wave | Underlying demographics that may change over years. Subgroup analysis in different age groups was done | External causes of death (ICD10 V01 to Y89.9) | Simplified relative risk (RR) approach ( ) | Deaths from external causes increased more sharply (RR = 1.18, CI 1.10 - 1.27) than from internal causes (RR = 1.04, CI 1.02 - 1.07) |
| Shaposhnikov et al. (1999-2007) | Four cities in North Russian (Archangelsk, Murmansk, Yakutsk, Magadan) | Long and short temperature waves defined by daily mean temperatures below the cold threshold (3rd centile) and daily mean temperature above the heat threshold (97th centile) |
Not mentioned | All external causes and all non-accidental (non-traumatic)deaths | Poisson distributions of daily deaths; X2 test for frequency tables based on city-specific RR estimates or fisher’s exact test for the pooled RR estimates | External causes of death could be an important contributing factor to the rise of total mortality during heat waves (they were responsible for about 8% of an increase in total mortality), while they are less important during cold waves (they caused about 3% of an increase) |
| Smirnova et al. (January 2010 to December 2012) | Russia (Nizhny Novgorod Oblast) | Extremely heat 6 week with T above 95th percentile and wildfire with increased air pollution | Season and other time-varying confounding factors | External cause of death (ICD10 codes: T58; T29 - 32, C76.8) | 2 × 2 and 2 × 3 contingency tables; the X2 (X squared) Pearson criterion | The period of AH (Abnormal Heat) was followed by an increase of mortality from external causes (p < 0.01) comparing to the summer 2011 |