Management of Clinical Variability in Radiotherapy Delivery: Explicit Treatment-Delivery Judgment and a Three-Layer Framework.
A Discussion Paper
DOI:
https://doi.org/10.7577/radopen.6721Keywords:
Cone-beam CT, Radiotherapy, Clinical variability, Patient safetyAbstract
Radiotherapy delivery is founded on standardization, protocol adherence, and quality assurance to ensure precision, reproducibility, and patient safety. However, clinical variability remains unavoidable because patient anatomy, organ filling, immobilization conditions, physiological status, image quality, and workflow constraints can change across treatment fractions. During daily cone-beam computed tomography (CBCT)-based verification, predefined protocols and tolerance thresholds provide essential safety boundaries but do not always determine the most appropriate action in complex or borderline situations. This discussion paper examines clinical variability in radiotherapy delivery and proposes a three-layer framework for making treatment-delivery judgment explicit and governable, distinguishing a protocol-based safety baseline, a guideline-based consensus domain, and a bounded judgment-based domain. An organizational learning loop is proposed to convert recurrent judgment scenarios into explicit institutional standards through documentation, peer discussion, interdisciplinary review, standard-operating-procedure refinement, audit, and education. The paper also considers how this framework relates to current radiotherapy practice, where radiation therapists operate within institutional and regulatory boundaries that differ across settings. The approach supports governance, patient safety, professional education, and accountability without redefining medical decision-making authority.
References
1. Halvorsen P, Gupta N, Rong Y. Clinical practice workflow in radiation oncology should be highly standardized. J Appl Clin Med Phys. 2019;20(4):6-9. doi:10.1002/acm2.12555.
2. Pawlicki T, Smith B, Hayman J, Ford E, eds. Safety is No Accident: A Framework for Quality Radiation Oncology and Care. 2nd ed. American Society for Radiation Oncology; 2019.
3. Baethge C, Goldbeck-Wood S, Mertens S. SANRA: A scale for the quality assessment of narrative review articles. Res Integr Peer Rev. 2019;4:5. doi:10.1186/s41073-019-0064-8.
4. Sonke JJ, Aznar M, Rasch C. Adaptive radiotherapy for anatomical changes. Semin Radiat Oncol. 2019;29(3):245-257. doi:10.1016/j.semradonc.2019.02.007.
5. Green OL, Henke LE, Hugo GD. Practical clinical workflows for online and offline adaptive radiation therapy. Semin Radiat Oncol. 2019;29(3):219-227. doi:10.1016/j.semradonc.2019.02.004.
6. Cho JH, Lee CG, Kang DR, et al. Positional reproducibility and effects of a rectal balloon in prostate cancer radiotherapy. J Korean Med Sci. 2009;24(5):894-903. doi:10.3346/jkms.2009.24.5.894.
7. van Lin ENJT, Hoffmann AL, van Kollenburg P, Leer JW, Visser AG. Rectal wall sparing effect of three different endorectal balloons in 3D conformal and IMRT prostate radiotherapy. Int J Radiat Oncol Biol Phys. 2005;63(2):565-576. doi:10.1016/j.ijrobp.2005.05.010.
8. Nishioka K, Shimizu S, Kinoshita R, et al. Evaluation of inter-observer variability of bladder boundary delineation on cone-beam CT. Radiat Oncol. 2013;8:185. doi:10.1186/1748-717X-8-185.
9. Brock KK, Mutic S, McNutt TR, Li H, Kessler ML. Use of image registration and fusion algorithms and techniques in radiotherapy: Report of the AAPM Radiation Therapy Committee Task Group No. 132. Med Phys. 2017;44(7):e43-e76. doi:10.1002/mp.12256.
10. Gillan C, Milne E, Harnett N, Purdie TG, Jaffray DA, Hodges B. Professional implications of introducing artificial intelligence in healthcare: An evaluation using radiation medicine as a testing ground. J Radiother Pract. 2019;18(1):5-9. doi:10.1017/S1460396918000468.
11. Huq MS, Fraass BA, Dunscombe PB, et al. The report of Task Group 100 of the AAPM: Application of risk analysis methods to radiation therapy quality management. Med Phys. 2016;43(7):4209-4262. doi:10.1118/1.4947547.
12. Ford EC, Fong de Los Santos L, Pawlicki T, Sutlief S, Dunscombe P. Consensus recommendations for incident learning database structures in radiation oncology. Med Phys. 2012;39(12):7272-7290. doi:10.1118/1.4764914.
13. Ford EC, Evans SB. Incident learning in radiation oncology: A review. Med Phys. 2018;45(5):e100-e119. doi:10.1002/mp.12800.
14. The Royal College of Radiologists. On Target 2: Updated Guidance for Image-Guided Radiotherapy. London: The Royal College of Radiologists; 2021.
15. Hattu D, Mannens J, Öllers M, van Loon J, De Ruysscher D, van Elmpt W. A traffic light protocol workflow for image-guided adaptive radiotherapy in lung cancer patients. Radiother Oncol. 2022;175:152-158. doi:10.1016/j.radonc.2022.08.030.
16. Buijs M, Pos F, Frantzen-Steneker M, Rossi M, Remeijer P, Koetsveld F. Take Action Protocol: A radiation therapist led approach to act on anatomical changes seen on CBCT. Tech Innov Patient Support Radiat Oncol. 2021;17:71-77. doi:10.1016/j.tipsro.2020.12.001.
17. Higgs J, Jones M, Loftus S, Christensen N, editors. Clinical Reasoning in the Health Professions. 4th ed. Amsterdam: Elsevier; 2018.
18. Schön DA. The Reflective Practitioner: How Professionals Think in Action. New York: Basic Books; 1983.
19. Dreyfus HL, Dreyfus SE. Mind Over Machine: The Power of Human Intuition and Expertise in the Era of the Computer. New York: Free Press; 1986.
20. Benner P. From Novice to Expert: Excellence and Power in Clinical Nursing Practice. Menlo Park, CA: Addison-Wesley; 1984.
21. Nonaka I, Takeuchi H. The Knowledge-Creating Company: How Japanese Companies Create the Dynamics of Innovation. New York: Oxford University Press; 1995.
22. Argyris C, Schön DA. Organizational Learning II: Theory, Method, and Practice. Reading, MA: Addison-Wesley; 1996.
23. Edmondson AC. Learning from failure in health care: Frequent opportunities, pervasive barriers. Qual Saf Health Care. 2004;13(Suppl 2):ii3-ii9. doi:10.1136/qhc.13.suppl_2.ii3.
24. McNair HA, Joyce E, O'Gara G, Jackson M, Peet B, Huddart RA, et al. Radiographer-led online image guided adaptive radiotherapy: A qualitative investigation of the therapeutic radiographer role. Radiography. 2021;27(4):1085-1093. doi:10.1016/j.radi.2021.04.012.
25. Shepherd M, Graham S, Ward A, Zwart L, Cai B, Shelley C, Booth J. Pathway for radiation therapists online advanced adapter training and credentialing. Tech Innov Patient Support Radiat Oncol. 2021;20:54-60. doi:10.1016/j.tipsro.2021.11.001.
26. Willigenburg T, de Muinck Keizer DM, Peters M, Claes A, Lagendijk JJW, de Boer HCJ, van der Voort van Zyp JRN. Evaluation of daily online contour adaptation by radiation therapists for prostate cancer treatment on an MRI-guided linear accelerator. Clin Transl Radiat Oncol. 2021;27:50-56. doi:10.1016/j.ctro.2021.01.002.
27. Reason J. Human Error. Cambridge: Cambridge University Press; 1990.
28. Hollnagel E, Woods DD, Leveson N, editors. Resilience Engineering: Concepts and Precepts. Aldershot: Ashgate; 2006.
29. Oliveira C, Barbosa B, Couto JG, Bravo I, Khine R, McNair H. Advanced practice roles of therapeutic radiographers/radiation therapists: A systematic literature review. Radiography. 2022;28(3):605-619. doi:10.1016/j.radi.2022.04.009.
30. Harnett N, Bak K, Zychla L, Gutierrez E, Warde P. Defining advanced practice in radiation therapy: A feasibility assessment of a new healthcare provider role in Ontario, Canada. Radiography. 2019;25(3):241-249. doi:10.1016/j.radi.2019.02.006.
31. Lamb J, Cao M, Kishan A, et al. Online adaptive radiation therapy: Implementation of a new process of care. Cureus. 2017;9(8):e1618. doi:10.7759/cureus.1618.
32. Aznar MC, Carrasco de Fez P, Corradini S, Mast M, McNair H, Meattini I, et al. ESTRO-ACROP guideline: Recommendations on implementation of breath-hold techniques in radiotherapy. Radiother Oncol. 2023;185:109734. doi:10.1016/j.radonc.2023.109734.
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