Meta-Analysis Systematic and Design Errors: Alcohol Use and Disease Outcomes

6.项目总结/摘要 本申请解决了广泛的挑战领域（05）比较有效性研究（CER）， 具体挑战主题，05-AA-101现有临床数据集的创新分析。 这个为期24个月的项目的重点是测试关于酒精之间的假设关联的假设 三种流行病引起的消费和疾病后果的风险 研究设计：队列研究、人群病例对照研究和医院病例对照研究。的 一般目的是检验流行病学研究中可能存在的系统误差的假设。Meta- 分析将用于确定这些研究中的不同方法和设计是否会产生过度偏倚 结果：（一）对某些疾病产生明显的酒精保护;（二）掩盖 潜在的统计学意义的关联;（iii）有助于“混合”的结果，违背了一个明确的 决议;和（iv）影响的规模和意义建立酒精疾病协会。所有 已知的流行病学研究，如适用，已分别评估了酒精使用和缺血性 将比较中风、痴呆/阿尔茨海默病、出血性中风和结肠直肠癌。 将测试以下假设：i）系统性误分类错误，其中“戒酒者”组 错误地包括那些由于年龄增长或健康状况不佳而减少或停止饮酒的人， 发现“轻度/中度”使用酒精“保护"某些疾病; ii）研究采用 前瞻性设计更容易出现系统性误分类错误，因此更有可能显示J- 形状曲线（即保护作用），而病例对照研究不太可能遭受系统性 错误分类错误，因此更有可能显示出积极的线性关联; iii）控制设计 在一系列不同的研究中，可能增加系统性误分类错误的特征将 使研究结果更加一致（例如，控制酒精消费量测量的接近度 疾病发生率，排除对照组中既存疾病的受试者）; iv）系统性 错误的分类错误将减少酒精之间正线性关联的大小和意义， 消费和疾病。 该项目将促进对酒精对一系列慢性疾病的贡献的理解， 改进对酒精所致死亡率和发病率估计。缔约国应澄清以下方面的证据依据： 临床实践的建议，并有助于了解国家和国际战略，以减少 酒精饮料的危害。

6. Project Summary/Abstract This application addresses broad challenge Area (05) Comparative Effectiveness Research (CER) and specific challenge topic, 05-AA-101 Innovative Analyses of Existing Clinical Datasets. The focus of this 24 month project is to test hypotheses regarding postulated associations between alcohol consumption and the risk of disease outcomes that have emanated from three types of epidemiological research designs: cohort studies, population case-control studies and hospital case-control studies. The general aim is to test hypotheses regarding possible systematic errors in epidemiological studies. Meta- analyses will be used to determine whether different methods and designs in these studies can unduly bias results towards: (i) creating apparent protection from alcohol use against some diseases; (ii) masking potentially statistically significant associations; (iii) contributing to 'mixed' outcomes that defy a clear resolution; and (iv) influencing the size and significance for established alcohol-disease associations. All known epidemiological studies, if applicable, that have evaluated alcohol use and, respectively, ischemic stroke, dementia/Alzheimer's, hemorrhagic stroke, and colorectal cancer will be compared. The following hypotheses will be tested: i) Systematic misclassification error, whereby 'abstainer' groups erroneously include people who had reduced or stopped drinking due to increasing age or ill-health, biases towards finding that 'light/moderate' use of alcohol 'protects' against certain disease; ii) Studies employing prospective designs are more prone to systematic misclassification error and hence more likely to show J- shape curves (i.e. protective effects), whereas case-control studies are less likely to suffer from systematic misclassification error and hence more likely to show positive linear associations; iii) Controlling for design characteristics likely to increase systematic misclassification error across a range of different studies will bring study outcomes into closer agreement (e.g. control for proximity of the measure of alcohol consumption to disease incidence, exclusion of subjects with pre-existing illness in comparison groups); iv) Systematic misclassification error will reduce the size and significance of positive linear associations between alcohol consumption and disease. The project will advance the understanding of alcohol's contribution to a range of chronic diseases and improve estimates of alcohol-attributable mortality and morbidity. It should clarify the evidentiary basis for advice from clinical practice and contribute understanding to national and international strategies to reduce the harm from alcoholic beverages.