Optimization of a Dosimetric Quality Assurance System for a Medical Linear Accelerator under ISO/IEC 17025 Accreditation: Measurement Stability Assessed by Uncertainty Analysis
Abstract
Background
Accurate dosimetry is essential for safe and effective radiotherapy. Although international guidelines are available, routine clinical practice does not always include a comprehensive evaluation of measurement uncertainty and methodological stability.
Purpose
This study presents a structured quality assurance system for medical linear accelerators, with particular emphasis on measurement uncertainty analysis as a tool for assessing the stability and robustness of dosimetric procedures.
Materials and Methods
The study was conducted on a fleet of 10 Varian linear accelerators operating in photon and electron energy ranges. Quality control procedures were developed in accordance with international recommendations (IAEA, AAPM, ESTRO) and implemented within an accredited system compliant with PN-EN ISO/IEC 17025. Measurement uncertainty was evaluated using Type A and Type B approaches, including repeatability, reproducibility, and long-term stability analyses.
Results
The implemented framework enabled quantitative evaluation of measurement uncertainty and confirmed compliance with acceptance criteria for all analyzed parameters. Reduced measurement variability and improved repeatability were observed across all monitored procedures.
Conclusions
The implementation of an accredited dosimetric quality assurance system significantly improved measurement consistency and clinical safety. Measurement uncertainty analysis proved to be an effective tool for monitoring stability and minimizing the risk of dosimetric errors in radiotherapy.
© 2026 Marzena Janiszewska, Maciej Raczkowski, published by Polish Society of Medical Physics
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.