Meta-analysis on the association between allergy and head and neck cancer.

*The Meta-RR was generated by a random effects model using the DersSimonian and Laird method if the heterogeneity was high to moderate (I2≥25%) and by a fixed effects model if the heterogeneity was low (I2Abbreviations: CI, confidence interval; meta-RR, meta-relative risk; n, number of studies.*当异质性为中至高水平（I²≥25%）时，采用德西蒙尼安-莱尔德法（DerSimonian and Laird method）结合随机效应模型生成荟萃相对风险（meta-RR）；当异质性较低（I²<25%）时，则采用固定效应模型。缩写说明：CI，置信区间（confidence interval）；meta-RR，荟萃相对风险（meta-relative risk）；n，纳入研究的数量。