CASE-COHORT STUDY OF MAMMOGRAPHY AND BREAST CANCER

减少昂贵的数据收集的统计技术将是 对癌症流行病学家很有价值。 这些方法包括减少 后续行动的持续时间和减少数据收集， 无信息的主题。 癌症死亡率的替代结果可能 大幅度减少后续行动的时间和数量， 参与大型干预研究。普伦蒂斯提出了 用于评估死亡率替代结果的有效性。他 还提出了一个病例队列设计，集中收集数据， 有影响力的主题，并减少对那些没有 利益的结果。这种设计考虑到比例风险 分析失效时间结果。 然而，这些方法尚未得到广泛接受。的 确定替代结果有效性的条件是 严格且难以测试。病例队列设计很少使用， 计算困难的方差估计器和缺乏软件， 符合模型。该提案演示了这两种方法的应用， 关于乳房X线摄影筛查在减少 乳腺癌死亡率病例队列设计将被证明是一种 使用观察数据评估癌症筛查的有效方法。 它还允许测试使用晚期乳腺癌作为治疗的有效性。 测量筛选有效性的替代结果。 人口包括94 656名40岁及以上的妇女， 在1982-88年期间在一个大型地区HMO注册。 有1144个 乳腺癌病例，包括126例随后死于乳腺癌的病例 癌随访将扩大到包括另外100例死亡。 病例队列分析将包括死亡率和晚期疾病， 结果。 晚期疾病的定义是不同的肿瘤组合， 阶段和规模。 晚期疾病作为替代的有效性 将通过统计模型检验死亡率。 软件将 开发允许交互式模型拟合。 研究结果和 将向流行病学家分发软件， 统计学家。

Statistical techniques that reduce costly data collection would be of great value to cancer epidemiologists. Such methods include reduction of duration of follow-up and reduction of data collection on relatively uninformative subjects. Surrogate outcomes for cancer mortality could substantially reduce the duration of follow-up and the number of participants in large intervention studies. Prentice has proposed criteria for assessing the validity of surrogate outcomes for mortality. He has also proposed a case-cohort design which concentrates data collection on influential subjects and reduces data collection on those without the outcome of interest. This design allows for a proportional hazards analysis of time to failure outcomes. Nonetheless, the methods have not found widespread acceptance. The conditions for determining the validity of the surrogate outcomes are stringent and difficult to test. The case-cohort design is seldom used due to a computationally difficult variance estimator and lack of software to fit the model. This proposal demonstrates application of both methods to existing data concerning the efficacy of mammography screening in reducing breast cancer mortality. The case-cohort design will be shown to be an efficient method for evaluating cancer screening using observational data. It also allows testing the validity of using advanced breast cancer as a surrogate outcome in measuring screening efficacy. The population consists of 94,656 women aged 40 and older who were enrolled in a large regional HMO in the period 1982-88. There were 1,144 incident breast cancer cases including 126 who subsequently died of breast cancer. Follow-up will be extended to include an additional 100 deaths. The case-cohort analysis will include mortality and advanced disease as outcomes. Advanced disease is defined by different combinations of tumor stage and size. The validity of advanced disease as a surrogate for mortality will be tested by the statistical model. Software will be developed allowing interactive model fitting. The study results and software will be disseminated to epidemiologists and applied statisticians.