Symptoms of respiratory tract infection and associated care-seeking in subjects with and without obstructive lung disease; The Tromsø Study: Tromsø 6

Table 1 Subjects invited to participate in the Tromsø 6 study

First visit
Age 30 – 39	10% random sample
Age 40 – 42	All residents
Age 43 – 59	40% random sample
Age 60 – 87	All residents
Attenders to the second visit of Tromsø 4^#	All residents if not included above
Second visit
Age 50 – 62	All attenders to first visit
Age 63 – 74	20% random sample of attenders to first visit
Age 75 – 84	All attenders to first visit
Attenders to the second visit of Tromsø 4^#	All attenders to first visit (in Tromsø 6)

^# The whole Tromsø population aged 25 years or more were invited to Tromsø 4 in 1994, and all the attending men aged 55–74 years and the attending women aged 50–74 years were invited to the second visit [12].

ISSN: 1471-2466