用成组病例对照研究方法进行儿童军团菌感染危险因素研究。通过多元逐步回归分析及非条件Ｌｏｇｉｓｔｉｃ回归模型分析筛选出年龄、季节、被动吸烟、频繁接触泥土及免疫抑制剂持续应用为军团菌感染的危险因素，因素的分级分析显示年龄、被动吸烟程度、免疫抑制剂持续应用与军团菌感染有剂量－反应关系。 Study on Risk Factors of Legionella Infection in Children with a Group Case Control Study. By means of multiple stepwise regression analysis and non-conditional logistic regression analysis, the risk factors of Legionella infection were identified by age, season, passive smoking, frequent contact with soil and immunosuppressive agents. The grading analysis showed that age, passive smoking, immunity Sustained use of inhibitors has a dose-response relationship with Legionella infection.