IAEA End-to-End Brachytherapy Dosimetry Audit
Overview
This project is part of an IAEA multi-centre end-to-end dosimetry audit for high-dose-rate Ir-192 gynaecological brachytherapy. Twenty-six centres irradiated an anthropomorphic phantom following their full clinical workflow, and radiochromic film measurements were compared against the doses calculated by each centre's treatment planning system (TPS). The analysis derives film/TPS dose ratios and correction factors per applicator material and anatomical region, and benchmarks them against Monte Carlo simulated total correction factors.
My role
Data analyst at the IAEA Dosimetry Laboratory. I designed and built the full analysis pipeline in Python: consolidating the raw measurement workbooks from all centres and both film-analysis systems, computing dose ratios and correction factors, performing the statistical analysis, generating all cohort-level figures, and producing an automated, self-contained HTML report card for each participating centre.
Methods & tools
Each centre was measured with two independent film-analysis systems (FilmQA Pro and Radiochromic) on four measurement planes, with audit points selected in the flattest part of the dose distribution. Centres were grouped by applicator material (plastic and titanium) and by region (lateral, bladder, rectum). The statistical analysis covered normality testing (Shapiro-Wilk), confidence intervals and t-tests, Gaussian and outlier analysis, tolerance and action levels, and Shewhart control charts. The pipeline was written in Python with numpy, scipy, matplotlib, and openpyxl, and is fully reproducible: every workbook, figure, and report regenerates from the raw data with a single sequence of scripts.
Why it matters
End-to-end audits test the entire brachytherapy chain, from imaging and planning to delivery, exactly as a patient would experience it. Deriving experimental correction factors and comparing them against Monte Carlo predictions helps establish realistic tolerance and action levels for an international audit methodology, and each centre receives a confidential report card benchmarking its results against the anonymized cohort.
Part of ongoing IAEA Dosimetry Laboratory work. See all Publications.