1;Preface;7
2;1 Accuracy Goals for Laboratory Tests;13
2.1;1.1 Accuracy and Precision;13
2.1.1;1.1.1 Definition;13
2.1.2;1.1.2 Imprecision as a Form of Error;14
2.2;1.2 Types of Error;14
2.2.1;1.2.1 Bias;14
2.2.2;1.2.2 Impact of Bias;16
2.3;1.3 Interference as a Type of Bias;18
2.4;1.4 References;20
3;2 Nature of Interferences;23
3.1;2.1 Definition;23
3.2;2.2 Nature of Interferences;23
3.3;2.3 Instrumentation;24
3.4;2.4 The Chemistry of the Absorbance of Light;27
3.5;2.5 References;32
4;3 The Nature of Icteric Interference;33
4.1;3.1 Source Information on Bilirubin Interference;33
4.2;3.2 Allen Correction as a Source of Bilirubin Interference;33
4.3;3.3 Bilirubin Interference with Oximetry;34
4.3.1;3.3.1 Co-oximetry Interference;36
4.3.2;3.3.2 Pulse Oximetry;37
4.3.3;3.3.3 Cerebral Oximetry;38
4.3.4;3.3.4 Interference with Methemoglobin;39
4.4;3.4 Chemical Reactions as a Cause of Bilirubin Interference;40
4.4.1;3.4.1 Bilirubin Reaction with Creatinine Methods;41
4.4.2;3.4.2 Bilirubin Reactions with Peroxidase Methods;43
4.5;3.5 References;44
5;4 The Nature of Lipemic and Turbidity Interferences;47
5.1;4.1 Types of Interferences;47
5.2;4.2 Lipemia Causes Turbidity;48
5.3;4.3 Lipemia Interference Mechanisms;49
5.3.1;4.3.1 Light Scattering;49
5.3.2;4.3.2 Lipoprotein Particles;52
5.3.3;4.3.3 Intralipid® and Lipemia Simulation;54
5.3.4;4.3.4 Empirical Studies in Lipemia Turbidity;55
5.4;4.4 Lipoprotein Particles and Lipemia;56
5.5;4.5 References;57
6;5 Measurement of Interference;59
6.1;5.1 A Typical Commercial Study;59
6.2;5.2 Guidelines for Interference Studies;60
6.3;5.3 Bilirubin;61
6.4;5.4 Intralipid®;62
6.5;5.5 Procedure to Make Five Concentrations;64
6.6;5.6 Interference Criteria;64
6.7;5.7 Data Analysis;66
6.8;5.8 References;72
7;6 Origin of Icteric Samples;75
7.1;6.1 The Origin of Bilirubin;75
7.2;6.2 Bilirubin Toxicity;77
7.3;6.3 Transport of Bilirubin in the Blood;77
7.4;6.4 Uptake of Bilirubin by the Liver;78
7.5;6.5 Clinical Aspects of Bilirubin;78
7.6;6.6 Neonatal Jaundice;79
7.7;6.7 Cholestasis;81
7.8;6.8 Hepatitis;82
7.9;6.9 Alcoholic Liver Disease;82
7.10;6.10 Hemolysis;83
7.11;6.11 Drug Induced Hyperbilirubinemia;83
7.12;6.12 Summary;84
7.13;6.13 References;84
8;7 Impact of Icterus;87
8.1;7.1 Introduction;87
8.2;7.2 Estimated Impacts Based on Interference Studies;87
8.3;7.3 Differential Interference with Different Bilirubin Isoforms;89
8.4;7.4 Non-spectrophotometric Icterus Interference;91
8.5;7.5 Resolving Icterus Interference;92
8.6;7.6 Summary;93
8.7;7.7 References;93
9;8 Origin of Lipemia and Turbidity;95
9.1;8.1 Lipoprotein Pathways;95
9.2;8.2 Classification of Hypertriglyceridemia;97
9.2.1;8.2.1 Frederickson Classification of Dyslipidemias;97
9.2.2;8.2.2 Obesity, Metabolic Syndrome and Diabetes;99
9.2.3;8.2.3 Alcohol;100
9.2.4;8.2.4 Nonalcoholic Fatty-liver Disorder;101
9.2.5;8.2.5 Medications;101
9.2.6;8.2.6 HIV Infection;101
9.2.7;8.2.7 Renal Disease;102
9.3;8.3 References;103
10;9 Impact of Lipemia/Turbidity;105
10.1;9.1 Introduction;105
10.2;9.2 Estimated Impacts Based on Interference Studies;107
10.2.1;9.2.1 Interference by Light Scattering;107
10.2.2;9.2.2 Interference by Volume Displacement;108
10.2.3;9.2.3 Interference by Lipid Partitioning;111
10.3;9.3 Summary;111
10.4;9.4 References;111
11;10 Endogenous Interferences in Clinical Laboratory Tests: Icteric, Lipemic and Turbid Samples;113
11.1;10.1 Interference Indices;113
11.2;10.2 Generating Interference Indices;113
11.2.1;10.2.1 Preparation of Standards;114
11.2.2;10.2.2 Data Collection and Deconvolution of Non-Target Interferences;115
11.2.2.1;10.2.2.1 Subtraction Using Selected Wavelengths;116
11.2.2.2;10.2.2.2 Index Calculation Using Derivative Spectrometry;117
11.2.3;10.2.3 Establishing Indices and Defining Ranges;119
11.3;10.3 Limitations;122
11.4;10.4 Summary;122
11.5;10.5 References;123
12;11 Reporting of Results;125
12.1;11.1 Introduction;1