Now featuring Sigma Metrics, Measurement Uncertainty & Total Error

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Statistical Metrics Report

We are delighted to announce the launch of Acusera 24.7 Live Online Version 1.6, now featuring automatic calculation of Measurement of Uncertainty, Total Error and Sigma Metrics.

Automatic Uncertainty of Measurement calculation; helping to meet ISO 15189:2012 requirements

The new Uncertainty of Measurement report automatically generates and displays the Measurement Uncertainty (UM) of all QC tests currently in use helping you to easily meet ISO 15189:2012 requirements.

To calculate UM, users must first enter the SEM of their intra assay precision (A) for each individual test and each level of control. This is based on a minimum of 20 replicates performed within the same run. Based on performance history, the Acusera 24.7 software will then automatically calculate the SD of the inter assay precision (B). The software then uses the following formula to automatically calculate the UM.

UM = √ A2 + B2

Since UM is calculated using SD and one SD is equal to 68% confidence on the Gaussian curve the software multiplies the UM by 1.96 to attain the Expanded UM and a confidence level of 95%.

Expanded UM = 1.96 x UM

 The report can be filtered by date to display data from a specific date range and may also be exported to CSV or printed.

Improve QC strategy design with our new Statistical Metrics Report

The Statistical Metrics Report facilitates enhanced performance assessment by incorporating several new metrics including; Measurement Uncertainty, Total Error (TE) and Sigma.

%Bias provides an indication of your laboratories performance compared to the peer group mean, while TE gives an indication of the overall error within a test system taking into account both imprecision and inaccuracy (bias). The availability of a Sigma Metric for each test is useful for designing an appropriate QC strategy. For example methods with a high Sigma score generally require less stringent QC strategies than those with a low Sigma value.

Sigma is a measure of the number of Standard Deviations (SDs) that fit within the total allowable limits. It is generated automatically by the software using the following formula:

Sigma =  %TEa – % Bias / %CV

  • TEa – Total Allowable Error
  • %Bias – Deviation from the target
  • %CV – Imprecision of the data

    Laboratory Quality Control