a decreasing trendP <0.001
an increasing trendP <0.001
Participants aged 15–34 yr and 35–49 yr showed a decreasing trend ( P <0.001) while those aged 50–64 yr and 65–80 yr showed an increasing trend ( P <0.001) between 2004 and 2013.
Participants aged 15–34 yr and 35–49 yr showed a decreasing trend ( P <0.001) while those aged 50–64 yr and 65–80 yr showed an increasing trend ( P <0.001) between 2004 and 2013.