Systematic review of prospective hazard analysis in radiation therapy

Prospective hazard analysis (PHA) was introduced to the wider medical physics community by the initiation of American association of physicists in medicine task group 100 in 2003. Since then, there has been increasing interest in the applicability of PHA to radiotherapy for the purpose of keeping patients safe and assessing the risks within the whole practice of radiotherapy. The purpose of this research was to review the PHA literature focusing on which techniques and technologies have been assessed, how they have been assessed, and what can be learnt.

The search for English language, peer-reviewed, full-text articles was conducted across five databases and the citations of three seminal papers using a common search strategy. The collation, filtration, and analysis of articles was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement reporting standard utilizing the following PICOS approach: Population: x-ray external beam radiation therapy, Intervention: prospective hazard analysis, Comparison: none, Outcome: patient safety, Study characteristics: details of applied technique.

689 unique studies were identified. 62 were determined to be eligible for inclusion. PHA has been applied to C-arm treatment systems (17), stereotactic radiosurgery (8), TomoTherapy (6), stereotactic body radiotherapy (5), Ethos (5), Halcyon (3), MRIdian (3), review activities (3), commissioning (2), unity (1), volumetric modulated arc therapy (1), surface guidance (1), CyberKnife (1), RefleXion (1) and other novel software and hardware systems (6). Disciplines involved in the studies were physicists (92%), physicians (75%), radiation therapists or dosimetrists (71%), external experts (38%), and facilitators (33%). Failure mode and effects analysis (FMEA) was used in 75% of studies, 10% used FMEA derived methods, 10% used system theoretic process analysis, and 5% used other methods. From the FMEA studies, 579 high-risk failure modes were extracted covering all aspects of the radiotherapy process, 50% applied to patient treatment delivery sessions and 25% applied to contouring and treatment planning. The mitigation strategies recommended by studies tended to add to the departmental workload.

62 studies were identified that used PHA in radiotherapy, within the included studies: patient journey was the most analyzed process, of the disciplines physicists were involved in the most studies, FMEA the most common technique, and the delivery of patient treatment was the greatest source of high-risk failure modes.