Details of the HAADs.

Abbreviations: WK = day of week, RA = raw admission numbers, NA = normalised admissions given as the number of admissions per 100,000 population, WS = wind speed at Melbourne airport at midday (units = km/h), WD = wind direction (i.e. from which the wind is blowing) at Melbourne airport at midday (units = degrees clockwise from North), EW = east-west component of the wind-speed at Melbourne airport at midday (units = km/h, positive means winds from the west), NS = north-south component of the wind-speed at Melbourne airport at midday (units = km/h, positive means winds from the south), PR = precipitation at Melbourne airport from 00:00h to 23:59h (units = mm), TM = temperature at Melbourne airport at midday (units = ° C), RH = relative humidity at Melbourne airport at midday (units = %), TS = thunderstorm reported at Melbourne airport from 00:00h to 23:59h (Y = yes, N = no), GR = daily grass pollen concentration at the University of Melbourne averaged from 16:00h the previous day to 16:00h the date stated (units = grains/m3), NG = daily non-grass pollen concentration, xlg = “lagged” average value of variable x over the 3 days prior to the given day (i.e. not including the value on the given day), O3 = daily average ozone (units = parts per billion by volume), PM2.5 = daily average particulate matter with an aerodynamic diameter less than 2.5 μ m (units = μ g/m3), NA = not available.