Text Box: THE NORMAL PREDICTED VALUE OF RESPIRATORY RESISTANCE BY MEANS OF IMPULSE OSCILLOMETRY IN CHILDREN OF 3 TO 14 YEARS OF AGE IN TIANJIN WAN LY, ZHANG Q, et al Department of Respiratory, Tianjin Children’s Hospital, Tianjin, China Objective: To study the characteristic of determination of impulse oscillometry (IOS) in children, and then create the normal reference values and equations of them in Tianjin region. Methods: 1220 healthy children were refered to the experment, 606 boys and 614 girls, aged from 3 to 14 years old. The respirtory resistance measured by Impulse Osicllometry System, which manufactured by Jergae Company in Germany, and than multiple stepwise regression and multiple linear regression equations were found for common used parameters. The influences of age, height and weight to the equations were analysed in the same time. Results: The height and weight were increased with age in the children, The total respiratory impedence, airway resistance and resonance frequency was decreased with age, whereas respiratory reactance was increased. Conclusion: The IOS measurements were closely correlated to height, weight and age, and normal prediced equations of children were created and were recommended. 1131