7 Validation of the Measurement Procedure . . . . . . . . . . . . . . . . . . . 87
7.1
Techniques, Methods and Measurement Procedures . . . . . . . . 89
7.2
Validation of the Analytical Procedure . . . . . . . . . . . . . . . . . . 90
7.3
Verification and Validation of Measuring Device . . . . . . . . . . 91
7.4
Validation of the Measurement Device Software . . . . . . . . . . . 91
7.5
Validation of Procedures for Processing the Results . . . . . . . . 91
7.6
Standardized Versus Laboratory-Developed Procedures . . . . . . 92
7.7
Measurement Techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
7.8
Validation of Measurement Procedure . . . . . . . . . . . . . . . . . . 96
7.9
Optimization and Validation of the Measurement
Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
7.10 Criteria for Selecting the Measurement Procedure . . . . . . . . . . 100
7.11 Validation Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
7.12 The Frequency of Revalidation . . . . . . . . . . . . . . . . . . . . . . . 103
7.13 Selected Parameters of Validation of the Measurement
Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
7.14 Selectivity and Specificity . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
7.15 Accuracy and Trueness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
7.16 Evaluation of the Accuracy and Precision . . . . . . . . . . . . . . . . 107
7.17 Evaluation of Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
7.18 The Limit of Detection and Quantitation . . . . . . . . . . . . . . . . 109
7.19 The Limit of Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
7.20 The Limit of Quantitation . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.21 Robustness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
7.22 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
8 Measurement Uncertainty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
8.1
Measurement and Its Uncertainty . . . . . . . . . . . . . . . . . . . . . . 117
8.2
The Reliability and Usefulness of the Measurement
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
8.3
Measurement Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
8.4
Error Versus Measurement Uncertainty . . . . . . . . . . . . . . . . . 122
8.5
Errors in Measurements of Chemical Quantities . . . . . . . . . . . 123
8.6
Types of Measurement Errors . . . . . . . . . . . . . . . . . . . . . . . . 124
8.7
Systematic Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
8.8
Random Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
8.9
Requirements Concerning the Uncertainty . . . . . . . . . . . . . . . 126
8.10 Determination of the Measurement Uncertainty . . . . . . . . . . . . 129
8.11 Evaluation of Uncertainty: Requirements in Chemical
Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
8.12 Modeling According to the ISO GUM Guide . . . . . . . . . . . . . 136
8.13 Evaluation of Standard Uncertainty for Each Identified
Component of the Measurement Uncertainty . . . . . . . . . . . . . . 137
Contents
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