188,274 research outputs found
Using Sigma metrics to establish analytical product performance requirements and optimize analytical performance of an in vitro diagnostic assay using a theoretical total PSA assay as an example
Introduction: Establishing analytical performance requirements for in vitro diagnostic (IVD) assays is a challenging process. Manufacturers try
to optimize analytical performance by choosing amongst many combinations of different product performance characteristics. Sigma metrics and
method decision charts can be helpful aids in choosing appropriate analytical performance requirements. The objective of this research was to demonstrate
the use of Sigma metrics and method decision charts to help establish analytical performance requirements and to optimize analytical
performance at medical decision concentrations for an IVD assay.
Materials and methods: A range of possible Sigma metrics were determined using three sources for total allowable error (TEa) and hypothetical
total PSA assay results. Method decision charts were created for each TEa source and used to identify the maximum precision and bias that the assay
could have to maintain sigma level performance of at least 3.
Results: To achieve a sigma performance level of at least 3 for a hypothetical total PSA assay, the maximum allowable coefficient of variation ranged
from 5.0% to 11.2% depending on the TEa source. To achieve a sigma performance level of at least 6, the maximum allowable coefficient of
variation ranged from 2.5% to 5.6% depending on the TEa source.
Conclusions: Using Sigma metrics and method decision charts when establishing analytical performance requirements can help manufacturers
choose product requirements that will optimize IVD assay product performance
Performance Analysis of Multihop Wireless Links over Generalized-K Fading Channels
The performance of multihop links is studied in this contribution by both analysis and simulations, when communicating over Generalized- () fading channels. The performance metrics considered include symbol error rate (SER), outage probability, level crossing rate (LCR) and average outage duration (AOD). First, the expressions for both the SER and outage probability are derived by approximating the probability density function (PDF) of the end-to-end signal-to-noise ratio (SNR) using an equivalent end-to-end PDF. We show that this equivalent end-to-end PDF is accurate for analyzing the outage probability. Then, the second-order statistics of LCR and AOD of multihop links are analyzed. Finally, the performance of multihop links is investigated either by simulations or by evaluation of the expressions derived. Our performance results show that the analytical expressions obtained can be well justified by the simulation results. The studies show that the channel model as well as the expressions derived in this paper are highly efficient for predicting the performance metrics and statistics for design of multihop communication links
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