利用LMS法建立全年龄段FEV1正常参考值

目的探讨一种建立肺功能全年龄段的正常参考值的方法。方法利用LMS法对4个中心共12829名正常健康人FEV1建立全年龄段正常参考值曲线和正常值下限，并对该模型进行评价。结果FEV1与身高、年龄之间存在密切关联，在校正身高影响之后，FEV1在全年龄段与年龄呈非线性关系，而且变异随着年龄变化而变化。LMS方法考虑个体间变异，适用于不服从正态分布的偏峰数据，而且还可以校正身高等其他因素的影响，计算得到的不同年龄的正常参考值最低下限更符合实际。结论LMS法是一种建立全年龄肺功能正常参考值的有效统计方法。

Establishment spirometric reference values across all ages based on LMS method

Objective The aim of the study was to show how Lambda-Mu-Sigma （LMS） method can be used to model age-related reference ranges, which is a new approach for establishing spirometric reference values across all age. Methods The prediction equations and the lower limit of normal （LLN） of FEV1 were established based on LMS method by analysis of 12 829 healthy,never-smoking adults aged 6 to 94 years. The good fittness of final model were inspected by SBC, Q-Q plots, worm plots and the density plots of residuals. Results The results show a strong multiplieative association between spirometry,height and age, with a large and nonlinear age effect across the age range. Variability also depends nonlinearly on age. By taking into account the age-dependency of variability,LMS method is more suitable for constracting reference values when the data departures from linearity, homoscedasticity and normality,and an appropriate LLN for age could be defined. Conclusions LMS method is a powerful technique for the establishment of spirometric reference values across all ages.