Fig. 4From: Effects of particulate matter (PM) on childhood asthma exacerbation and control in Xiamen, ChinaOdds ratiosof asthma exacerbation estimated for the exposure days to PM2.5 and PM10.Panel (a): Exposure days to PM2.5 within one week. Panel(b): Exposure days to PM2.5 within two weeks. Panel(c): Exposure to PM10 within one week. Panel(d): Exposure to PM10 within two weeksBack to article page