This analysis used data from 1672 participants of the 2004 TAHS postal
survey, with 601 participants in Launceston and 1071 participants in
Hobart. Participants were selected if the place of residence at the time of
the 2004 postal survey was within the urban area of either city. There
were fewer participants in Launceston, as it is a smaller city than Hobart.
The postal surveywas used to collect demographic data about participants
and dichotomous responses to questions about self-reported respiratory
symptoms experienced over the previous 12 months.