1.1本规程建立了统一标准，用于估算和表示D19水委员会适用试验方法的精度和偏差。原则上，本规程涵盖了所有测试方法。 1.2除1.4、1.5和1.6中的规定外，本实践要求任务组提出一种新的测试方法，以进行协作研究，从中可以制定精度声明（总体和单操作员标准偏差估计）和偏差。 该实践为任务组在规划和进行精度和偏差的确定方面提供了一般指导。 1.3本实践还为任务组进行有限规模的协作研究（称为 “ 可比性研究 ” )对于已修订的试验方法，当此类修订包括实质性修改时。实质性修改的示例可能包括但不限于强制或允许的仪器、试剂、反应时间等的更改。 1.3.1方法范围内适用水基质的变化可能构成本条款下的实质性修改。然而，要认识到，即使是最初的协作研究也可能没有使用该方法中指定的所有各种矩阵类型 ’ s原始范围。 1.3.2如第7节所述，被认为值得额外合作测试的方法浓度范围扩展（即使没有方法修改，否则将被视为实质性修改）应要求进行全面的合作研究。 1-7.5，但仅在代表扩展范围的Youden对浓度下。注意，这种协作研究可能只涉及单个可复制矩阵中的单个样本Youden配对研究。 1.3.3试验方法的修订是否包括实质性修改，应由委员会协商一致决定。 1.4如果由于试验方法的性质或样品的不稳定性，全面合作研究在技术上不可行，则最大可行比例- 应进行向下协作研究，为估计整体和单个操作员的标准偏差提供尽可能好的有限基础。 1.4.1可接受的缩小研究示例为小组委员会D19.24就微生物方法进行的局部研究，因为固有的样品不稳定性。这些研究涉及六名或六名以上完全独立的本地分析师，他们可以在约定的时间开始分析均匀样本。 1.4.2如果均匀样品在任何情况下都不可行，则应提供一份- 操作员精度将满足本规程的要求。只要可能，该声明应根据独立多个操作员生成的数据编制，每个操作员对独立样本（特定基质类型）进行重复分析，这些样本通常在规定的浓度范围内（见7.2.5.2）( 3. )). 1.4.3本规程不适用于涉及对特定成分和特性进行连续采样或连续测量的方法。 1.4.4本规程也不适用于明渠流量测量。 1.5在进行研究时，满足本实施规程版本要求的合作研究将继续被视为每个试验方法中所需精度和偏差声明的充分基础。如果研究不满足当前协作研究的最低要求，则应在精度中包括一份列出研究缺陷的声明和对本段的引用- 并将偏差声明作为免除当前要求的依据。 1.6本段涉及1.4或1.5项下不明确接受的特殊豁免。在D19委员会根据结果顾问和D19委员会执行小组委员会技术操作科的建议批准后，一份声明将满足ASTM的两项要求，该声明给出了无法达到本规程所有或特定点的令人信服的理由 (1) 以及本规程的相关要求。此外，D19委员会可通过主要委员会投票批准发布 “ 预备性的 ” 不超过5年的标准方法。初步标准必须至少包含单操作员精度和偏差声明，以及基于单操作员数据的质量控制部分。初步标准的发布取决于该标准的完整D2777合作研究设计的批准。 本段授权的精度和偏差声明应包括D19委员会批准的日期。 1.7根据ASTM表格和样式手册A21.2.3节，委员会可推迟新方法的实验室间研究，并在精度和偏差部分包含一项临时声明，该声明仅涉及单操作员精度( “ 重复性 ” ). 本声明自首次发布之日起五年内有效。在这种情况下，应根据第7节进行单个实验室研究。 6. 1.8在第12节中，本规程展示了以下示例性精度和偏差声明格式:( 1. )产生数值测量的试验方法( 2. )根据程序中规定的标准，产生成功或失败的非数值报告的试验方法，以及( 3. )规定使用另一种ASTM试验方法中的程序的试验方法，仅需进行微不足道的修改。 1.9所有研究，即使是不符合第1.4节至第1.8节某些要求的研究，在进行前（见第8节）和完成后（见第13节）均应获得结果顾问的批准。 1.10本规程满足规程的QC要求 D5847 . 1.11本实践的目的是，任务组尽一切努力保留其循环研究中的所有数据。除非有确凿证据表明价值被排除，否则不应排除价值。结果顾问应与任务组密切合作，以实现这一目标。 ====意义和用途====== 遵循这一实践应产生精度和偏差声明，任何实验室都可以通过适当使用所研究的测试方法来实现。 这些精度和偏差声明为测试方法质量控制部分使用的通用限值提供了基础。或者，检测和定量值提供了大多数实验室应能够实现可靠检测并满足预期最低精度（表示为相对标准差）的估计水平。 该方法规定了测试方法适用的矩阵。协作测试证实了写作- 在测试设计的限制范围内。广泛测试只能使用代表性矩阵，因此结果不能暗示普遍适用性。 协作研究的基本假设是，测试的基质、测试的浓度和参与实验室是对书面测试方法的范围和适用性的代表性和公平评估。

1.1 This practice establishes uniform standards for estimating and expressing the precision and bias of applicable test methods for Committee D19 on Water. In principle, all test methods are covered by this practice. 1.2 Except as specified in 1.4, 1.5, and 1.6, this practice requires the task group proposing a new test method to carry out a collaborative study from which statements for precision (overall and single-operator standard-deviation estimates) and bias can be developed. This practice provides general guidance to task groups in planning and conducting such determinations of precision and bias. 1.3 This practice also provides guidance to task groups for conducting limited-scale collaborative studies (known as “ comparability studies ” ) for test methods that have been revised, when such revision includes substantive modifications. Examples of substantive modifications may include, but are not limited to, changes in mandatory or allowable instrumentation, reagents, reaction times, etc. 1.3.1 Changes to applicable water matrices in the Scope of a method may constitute a substantive modification under this provision. However, recognize that even the original collaborative study may not have used all the various matrix types specified in the method ’ s original Scope. 1.3.2 A method's concentration-range extension that is deemed to merit additional collaborative testing (even without a method modification that would otherwise be considered substantive) shall require a full collaborative study, as described in Sections 7.1-7.5, but only at Youden-pair concentrations representative of the extended range. Note that such a collaborative study could involve as little as a single-sample Youden-pair study in a single reproducible matrix. 1.3.3 Whether a revision to a test method includes substantive modification shall be determined by consensus of the Committee. 1.4 If a full-scale collaborative study is not technically feasible, due to the nature of the test method or instability of samples, the largest feasible scaled-down collaborative study shall be conducted to provide the best possible limited basis for estimating the overall and single-operator standard deviations. 1.4.1 Examples of acceptable scaled-down studies are the local-area studies conducted by Subcommittee D19.24 on microbiological methods because of inherent sample instability. These studies involve six or more completely independent local-area analysts who can begin analysis of uniform samples at an agreed upon time. 1.4.2 If uniform samples are not feasible under any circumstances, a statement of single-operator precision will meet the requirements of this practice. Whenever possible, this statement should be developed from data generated by independent multiple operators, each doing replicate analyses on independent samples (of a specific matrix type), which generally fall within specified concentration ranges (see 7.2.5.2 ( 3 )). 1.4.3 This practice is not applicable to methodology involving continuous sampling or continuous measurement, or both, of specific constituents and properties. 1.4.4 This practice is also not applicable to open-channel flow measurements. 1.5 A collaborative study that satisfied the requirements of the version of this practice in force when the study was conducted will continue to be considered an adequate basis for the precision-and-bias statement required in each test method. If the study does not satisfy the current minimum requirements for a collaborative study, a statement listing the study's deficiencies and a reference to this paragraph shall be included in the precision-and-bias statement as the basis for an exemption from the current requirements. 1.6 This paragraph relates to special exemptions not clearly acceptable under 1.4 or 1.5. With the approval of Committee D19 on the recommendation of the Results Advisor and the Technical Operations Section of the Executive Subcommittee of Committee D19, a statement giving a compelling reason why compliance with all or specific points of this practice cannot be achieved will meet both ASTM requirements (1) and the related requirements of this practice. In addition, Committee D19, through a Main Committee ballot, may approve publication of a “ Preliminary ” Standard Method for a period not to exceed 5 years. Preliminary Standards must contain a minimum of a single-operator precision-and-bias statement and a Quality Control section based on the single operator data. Publication of a Preliminary Standard is conditional on the approval of a full D2777 collaborative study design for the standard. Precision-and-bias statements authorized by this paragraph shall include the date of approval by Committee D19. 1.7 Per Section A21.2.3 of the ASTM Form and Style Manual the committee may delay an interlaboratory study for a new method and include a temporary statement in the Precision and Bias Section that addresses only single operator precision ( “ repeatability ” ). This statement is valid for five years from the initial publication date. In this case, a single laboratory study shall be conducted in accordance with Section 7.6. 1.8 In Section 12 this practice shows exemplary precision-and-bias-statement formats for: ( 1 ) test methods yielding a numerical measure, ( 2 ) test methods yielding a non-numerical report of success or failure based on criteria specified in the procedure, and ( 3 ) test methods specifying that procedures in another ASTM test method are to be used with only insignificant modifications. 1.9 All studies, even those exempt from some requirements under Sections 1.4 through 1.8, shall receive approval from the Results Advisor before being conducted (see Section 8) and after completion (see Section 13). 1.10 This practice satisfies the QC requirements of Practice D5847 . 1.11 It is the intent of this practice that task groups make every effort to retain all the data from their round-robin studies. Values should not be eliminated unless solid evidence exists for their exclusion. The Results Advisor should work closely with the task groups to effect this goal. ====== Significance And Use ====== Following this practice should result in precision-and-bias statements that can be achieved by any laboratory properly using the test method studied. These precision-and-bias statements provide the basis for generic limits for use in the Quality Control section of the test method. Optionally, the detection and quantitation values provide estimates of the level at which most laboratories should be able to achieve confident detection and meet the minimum precision (expressed as relative standard deviation) expected. The method specifies the matrices for which the test method is appropriate. The collaborative test corroborates the write-up within the limitations of the test design. An extensive test can only use representative matrices so that universal applicability cannot be implied from the results. The fundamental assumption of the collaborative study is that the matrices tested, the concentrations tested, and the participating laboratories are a representative and fair evaluation of the scope and applicability of the test method as written.