Table 1: Description of the study population

	n	%
Base population*	2,350	100
Participated in both surveys	1,405	59.8
Participated in survey 1990/91 but not in 2002/03	377	16.0
Participated in survey 2002/03 but not in 1990/91	181	7.7
Did not participate in any survey	387	16.5

* 147 individuals had died between the two surveys.