Safer radiation therapy treatment resulting from an equipment transition: A mixed-methods study

To realize individualized safe radiation therapy, reliable treatment equipment is essential in combination with a system-level improvement approach. We hypothesized that implementation of a system that integrated all required treatment equipment would result in improved safety and stability of the irradiation treatment process.Seven accelerators, portal imaging, and the treatment planning software were replaced by an integrated system that included 6 accelerators. The number of reported safety incidents and root causes were recorded between 2010 and 2014. Time series analysis was performed, and quantitative results were explored by structured interviews. Additionally, downtime was recorded.From January 2010 to July 2014, 5085 incidents were reported. Reports related to the accelerators decreased from 33% (2010) to 20% (2013-2014) of total reports, whereas the number of delivered fractions per accelerator increased by 20% (2010: 643 per month; 2013: 795 per month). Reports related to portal imaging decreased from 16.5 reports per month (2010) to 3.1 (2013-2014). Of these portal imaging reports, 316 had at least 1 technical cause in 2010, which decreased to 13 in 2013-2014. Interviewees attributed the decreased reporting to the equipment transition, not to decreased safety awareness. Downtime decreased by 46%, from 5.4% in 2010 to 2.9% in 2013.The number of reported accelerator- and portal imaging-related incidents decreased significantly, whereas safety awareness remained stable. In addition, accelerator downtime decreased, possibly resulting in less rescheduling of patients and fewer disruptions of work processes. Therefore, we conclude that the risk for serious safety incidents and patient harm decreased after implementation of the new integrated system.