Comparison of risk factors for recurrent respiratory infections between urban and rural preschool children in Yiwu, China.Yan Zou, Hong-Xing Jin, Rong-Shan Wang, Hai-Feng Li, Pei-Gang JinWorld journal of pediatrics : WJP2012BACKGROUND Many studies have shown an association between the risk of increased recurrent respiratory infections and socioeconomic and fostering factors, but often only a few risk factors have been… (More)