title: Methods comparison.
abstract: The current report discusses the process in which a methods comparison study in the National Animal Health Laboratory Network is performed. Specific details are provided for designing and analyzing studies intended to evaluate analytical sensitivity, efficiency, analytical specificity, cross-contamination, repeatability, operator variability, and to compare the performance of methods using diagnostic samples. As an example, a case study is presented comparing the performance of a candidate reverse transcription polymerase chain reaction (RT-PCR) chemistry to the current RT-PCR chemistry in use when the assay was originally validated. The present study revealed that, for all of the validation factors evaluated, the candidate method performed at least as well and generally better than the current method. The candidate method was, therefore, deemed fit for the original intended purpose of the current method and rendered acceptable for use. A discussion of the case study is intended to further motivate consideration of the study designs chosen.
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Monica M
authors.initials: MM
authors.lastname: Reising
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Kate R
authors.initials: KR
authors.lastname: Schumann
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Beate M
authors.initials: BM
authors.lastname: Crossley
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Patricia S
authors.initials: PS
authors.lastname: Glas
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Richard H
authors.initials: RH
authors.lastname: Jacobson
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Kathy L
authors.initials: KL
authors.lastname: Toohey-Kurth
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Janice C
authors.initials: JC
authors.lastname: Pedersen
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: David
authors.initials: D
authors.lastname: Siev
authors.affiliation: Center for Veterinary Biologics, Policy Evaluation and Licensing, Statistics Section, Ames, IA (Reising, Siev).|National Veterinary Services Laboratories, Foreign Animal Disease Diagnostic Laboratory, Plum Island, NY (Schumann, Glas).|California Animal Health and Food Safety Laboratory, Department of Medicine and Epidemiology, University of California, Davis, CA (Crossley).|Animal Health Diagnostic Center, Cornell University, Ithaca, NY (Jacobson).|Wisconsin Veterinary Diagnostic Laboratory and Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI (Toohey-Kurth).|National Veterinary Services Laboratories, Diagnostic Virology Laboratory, Ames, IA (Pedersen).|Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA (Martin).
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Martin
mesh_terms: D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods / Q000592:standards / Q000662:veterinary*; D012680:Sensitivity and Specificity; D014730:Veterinary Medicine / Q000379:methods*
keywords: Methods comparison; polymerase chain reaction; validation