PDA TR60 附录1 决定批次的统计学方法.pdfVIP

8.0 Appendices 附件 8.1 Appendix 1: Statistical Methods for Determining the Number of Lots 附件1：决定批数量的统计学方法 Listed below are statistical approaches used to determine the number of lots that may be required at the PPQ stage. Other approaches may also be suitable. As there is no standard industry approach to statistically determine the number of lots, multiple options are offered. This section will provide applied statistical methods for determining the number of lots. It will also stimulate further discussion on this issue. Regardless of the number of lots selected and the acceptance criteria used, the data collected during PPQ as well as CPV should be statistically analyzed to help understand process stability, capability, and within (intra-) and between-lot (inter-lot) variation. 下面列举的是在PPQ 阶段用于决定批次数量的统计学方法。除此之外的方法当然也可能适 用。因为行业中并没有从统计学上决定批次的数量的标准方法，所以其他多种方法同样可以 提供。本章节将提供决定批次数量实用的统计学方法，并鼓励在这个方面更加深入的讨论。 无论选择的批次数量以及采用的可接受标准是多少，PPQ 中收集的数据都应进行统计分析 以帮助理解工艺的稳定性、工艺能力以及批内和批间的变异。 8.1.1 Average Run Length (ARL) to detect a p×100% lot failure rate 用以检测批失败率 （p×100%）的平均运行长度 （ARL ） The average number of lots until the first lot failure is ARL =1/p. where p is the lot failure rate that is important to detect. 直到出现第一批失败的平均批数量 （ARL ）=1/p,其中p 为批失败率，检测出p 是很重要的。 Example: A lot failure rate of 20% is deemed unacceptable for a given process. A lot failure rate of 20% would be detected on average in 1/0.2=5 lots. 例子：往往一个工艺出现 20% 的批失败率是被认为不可接受的。而 20% 的批失败率可 以从平均1/0.2=5 批中被检测出。 Common choices for p would be 25%, 20%, 10%, and 5%, depending on the other factors given earlier (e.g., prior knowledge, risk, production rate) Five (5%) would generally be the tightest value to consider since a process running right at the Acceptance Quality Limit is still expected to have a