Odds ratios or p_values from individual observational studies can be combined to examine a common cause_effect research question in meta_analysis. However, reliability of individual studies used in meta_analysis should not be taken for granted as claimed cause_effect associations may not reproduce. An evaluation was undertaken on meta_analysis of base papers examining gas stove cooking, including nitrogen dioxide, NO2, and childhood asthma and wheeze associations. Numbers of hypotheses tested in 14 of 27 base papers, 52 percent, used in meta_analysis of asthma and wheeze were counted. Test statistics used in the meta_analysis, 40 odds ratios with 95 percent confidence limits, were converted to p_values and presented in p_value plots. The median and interquartile range of possible numbers of hypotheses tested in the 14 base papers was 15,360, 6,336_49,152. None of the 14 base papers made mention of correcting for multiple testing, nor was any explanation offered if no multiple testing procedure was used. Given large numbers of hypotheses available, statistics drawn from base papers and used for meta-analysis are likely biased. Even so, p-value plots for gas stove_current asthma and gas stove_current wheeze associations show randomness consistent with unproven gas stove harms. The meta-analysis fails to provide reliable evidence for public health policy making on gas stove harms to children in North America. NO2 is not established as a biologically plausible explanation of a causal link with childhood asthma. Biases_multiple testing and p-hacking_cannot be ruled out as explanations for a gas stove_current asthma association claim. Selective reporting is another bias in published literature of gas stove_childhood respiratory health studies. Keywords gas stove, asthma, meta-analysis, p-value plot, multiple testing, p_hacking

翻译：通过元分析，可将单次观察性研究的优势比或p值合并，以检验共同因果效应假设。然而，不应默认元分析所基于的单次研究具有可靠性，因为声称的因果关联可能无法复现。本研究对考察燃气灶烹饪（包括二氧化氮NO2）与儿童哮喘及喘息关联的基础论文展开元分析评估。在27篇用于哮喘和喘息元分析的基础论文中，对14篇（占52%）检验的假设数量进行了统计。将元分析中使用的检验统计量（含95%置信区间的40个优势比）转换为p值并绘制p值图。14篇基础论文中可能检验的假设数量中位数为15,360，四分位距为6,336至49,152。这14篇论文均未提及多重检验校正，也未对未采用多重检验程序作出任何解释。鉴于可获取的假设数量庞大，从基础论文中提取并用于元分析的统计量可能存在偏倚。即便如此，燃气灶-当前哮喘及燃气灶-当前喘息关联的p值图显示，其随机性符合"燃气灶危害尚未证实"的结论。该元分析未能为北美地区燃气灶对儿童危害的公共卫生决策提供可靠证据。NO2尚未被确立为与儿童哮喘存在生物学合理性的因果关联。多重检验偏倚与p值篡改不能排除为解释燃气灶-当前哮喘关联声称的替代机制。选择性报告是燃气灶-儿童呼吸健康研究文献中的另一偏倚来源。关键词：燃气灶，哮喘，元分析，p值图，多重检验，p值篡改