EXPERIMENTAL DESIGN AND DATA ANALYSIS METHODOLOGY FOR ANIMAL EXPERIMENTS

该项目涉及的是联合国系统内的统计方法问题。 实验动物实验的设计、分析和解释。 具体研究工作包括：（1）背景肿瘤 在当前研究中，F344大鼠的发生率远高于在 十几年前 肿瘤发生率的增加伴随着 存活率和体重增加。 造成这些的因素 肿瘤发生率的增加包括尸检时检查的组织更多， 研究、组织病理学诊断的变化、遗传漂变和饮食 因素(2)方法学的发展允许生存调整 分析肿瘤发病率，同时避免 关于肿瘤致死率或死亡原因的假设。 如果约束是 置于描述基础肿瘤发作/死亡的转换率上 过程中，分析是可行的，只有一个牺牲时间（例如，的 终末杀灭）。 最有希望的限制是规定 在有和没有病毒的动物死亡率之间的恒定差异 感兴趣的肿瘤。(3)的一些统计特性 检查计算机测量精子参数如速度。 这些数据的分析由于有多个精子而变得复杂。 同一种动物，在动物体内产生精子的巢状结构 治疗 与该项目相关的未来研究包括检查 最大耐受剂量与啮齿动物致癌性之间的关系，以及 通过计算机仿真，将现有方法与入射角法进行了比较， 根据2004 - 2005年死亡率之间的恒定差异进行的分析 无肿瘤和携带肿瘤的动物。

This project is concerned with statistical methodology issues in the design, analysis, and interpretation of laboratory animal experiments. Specific research efforts include: (1) It was shown that background tumor rates in F344 rats a much higher in current studies than in those conducted a decade ago. The increased tumor rates are accompanied by decreased survival and increased body weights. Factors responsible for these increasing tumor rates include more tissue examined at necropsy in current studies, changes in histopathology diagnosis genetic drift, and dietary factors. (2) Methodology was developed to permit a survival-adjusted analysis of tumor incidence rates while avoiding the need to make assumptions about tumor lethality or cause of death. If constraints are placed on the transition rates describing the underlying tumor onset/death process, the analysis is feasible with only one sacrifice time (e.g., the terminal kill). The most promising restriction was the one that specified a constant difference between the death rates for animals with and without the tumor of interest. (3) Some of the statistical properties of computerized measurements sperm parameters such as velocity were examined. The analysis of such data complicated by having multiple sperm from the same animal, giving the nested structure of sperm within animal within treatment. Future research related to this project includes examining the relationship between maximum tolerated dose and rodent carcinogenicity, and comparing by computer's simulation existing methods with the incidence analysis based on constant differences between the death rates for tumor-free and tumor-bearing animals.