Results Taking the results from Mantel-Haenszel method as standard reference, the point and interval estimators of adjusted relative risks obtained from modified poisson regression were similar to those, while the ordinary poisson regression produced very conservative confidence interval estimators. 结果以分层的Mantel-Haenszel法为标准参照,修正poisson回归对aRR点和区间估计均较为理想,普通poisson回归的aRR区间估计偏于保守。