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Updated: Sep 16, 2025
06:08
A Cognitive Fusion-guided Prostate Biopsy Using Multiparametric Magnetic Resonance Imaging and Transrectal Ultrasound
Published on: March 21, 2025
382
Measurement Uncertainty and the Prostate Health Index-A Review
Ian Farrance1, Robert Frenkel2
1Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia.
The Journal of Applied Laboratory Medicine
|July 11, 2025
Summary
Measurement uncertainty (MU) for calculated values, like the prostate health index (PHI), is crucial for clinical interpretation. The Guide to the Expression of Uncertainty in Measurement (GUM) provides a more accurate MU estimate than internal quality control (IQC) methods, especially when including correlation terms.
Area of Science:
- Clinical chemistry
- Laboratory medicine
- Measurement science
Background:
- Many medical laboratory values are calculated, not directly measured.
- Measurement uncertainty (MU) of calculated quantities is vital for clinical interpretation but often overlooked.
- The prostate health index (PHI) aids prostate cancer assessment.
Purpose of the Study:
- To evaluate the measurement uncertainty (MU) of the prostate health index (PHI) using the Guide to the Expression of Uncertainty in Measurement (GUM) procedure.
- To compare the GUM approach with a novel method using internal quality control (IQC) for MU estimation.
- To demonstrate the impact of correlation terms on MU calculations for PHI.
Main Methods:
- Applied the GUM procedure for a comprehensive MU evaluation of PHI.
- Calculated MU for PHI using both GUM and a direct IQC method.
- Incorporated correlation terms within the GUM framework.
Main Results:
- The GUM approach, with correlation, yielded a relative standard uncertainty of 3.60% for a mean PHI of 24.48.
- The direct IQC procedure resulted in a higher relative standard uncertainty of 7.2%.
- MU without correlation using GUM was 5.99%, highlighting the influence of correlation terms.
Conclusions:
- The GUM approach is superior for calculating PHI's MU, particularly when correlation is included.
- Direct IQC methods for MU estimation can overestimate uncertainty and do not account for correlations.
- Accurate MU assessment is essential for reliable clinical interpretation of calculated diagnostic values.
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