Table 1.

Sample characteristics for the 2004 and 2007 surveys

	2004	2007
N (response rate)	6 677 (43.3%)	11 085 (35.2%)
Proportion male	32.1%	30.8%
Proportion higher ed.	29.0%	35.5%
Mean age (st. dev.) in years	39.5 (12.4)	41.0 (12.7)
Proportion one consultation	7.7%	14.5%