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Table 2 explanatory variables used in all models.

From: Vegetation fire smoke, indigenous status and cardio-respiratory hospital admissions in Darwin, Australia, 1996–2005: a time-series study

Variable Description
Lagged PM10 Estimated ambient PM10 for each single-day lag 0, 1, 2 or 3 in (μg/m3)
Indigenous An index of counts for indigenous status where indigenous = 1 and non-indigenous = 0
Time Time in days, represented by a natural cubic spline with 40 df (4 df per dry season)
AvDailyTemp Average daily temperature (calculated by averaging the max and min temperatures), in Degrees Celsius (°C), with 6df
AvDailyTempLag1-3 Moving three-day averages of daily temperatures (lags 1, 2 and 3), with 6df
RHumAv Average daily relative humidity in percent (%) with 3df
RHumAvLag1-3 Moving three-day averages of daily relative humidity (lags 1, 2 and 3), with 3 df
DOW Day of the week. Factor with 7 levels
FluEpidemic Influenza epidemics. Dummy for days above the 90th centile
ICD10change The change between ICD editions. Dummy variable indicating the changeover
Holidays Dummy variable for public holidays
Population The estimated yearly population for indigenous or non-indigenous residents included as an offset