an increasing trendP < 0.001
D3 smokers showed an increasing trend between 2000 and 2010, following adjustment (GLF, P < 0.001; HSE, P = 0.04) with no significant trend found for D1 and D2.
D3 smokers showed an increasing trend between 2000 and 2010, following adjustment (GLF, P < 0.001; HSE, P = 0.04) with no significant trend found for D1 and D2.