Quality and Safety Improvement in Radiation Oncology

Watershed Accidents in Radiation Oncology

One way to view the issue of quality and safety in radiotherapy is to consider the serious accidents that have garnered the attention of the community and occasionally the media. The purpose of such an exercise is to understand the error pathways involved and prevent such events in the future. To this end, Table 12.1 summarizes selected watershed accidents in Radiation Oncology. Of particular note is the tragic death of Scott Jerome Parks, a patient with oropharyngeal cancer who received treatment in New York and was given a large radiation overdose. His story was reported in the U.S. national news media in 2010 and galvanized support for improved safety in radiation therapy.

Further material and information on accidents in radiation therapy can be found in International Atomic Energy Agency (IAEA) Safety Report No. 17 from 2000, which gives a brief account of 92 incidents. In the United States various public records are available, including through the U.S. Nuclear Regulatory Commission (NRC) Agencywide Documents Access and Management System (ADAMS), a searchable repository of public documents of medical events involving by-product materials ( https://forms.nrc.gov/reading-rm/adams.html#web-based-adams ), and the Manu­facturer and User Device Experience (MAUDE) database ( http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/search.cfm ) from the Food and Drug Administration (FDA), where information on reported device errors is held.

The overview in Table 12.1 focuses on serious radiation therapy accidents (i.e., catastrophic failures), but it must be recognized that less serious failures are much more common in clinical practice. Such errors are often discussed in the context of “quality of care” as opposed to patient safety. “Quality” and “safety,” however, are intermixed concepts in medicine. That is, “low quality care” (care that is deficient in some way) is usually also unsafe care, and vice versa. This is different from many other industries where one can deliver a low quality product (e.g., a car) that may not be, in itself, unsafe. Dunscombe et al. have argued that quality and safety are part of a Gaussian-like spectrum (the most unsafe care lying on the tails of the distribution) and have estimated that in the United States “approximately 20,000 patients per year have their outcome compromised to some unknown extent by poor-quality radiotherapy.” Objective estimates of error rates in Radiation Oncology are difficult to formulate. Approximate estimates indicate a rate of misadministrations of 0.2%, though this is likely an underestimate.

The Quality Gap and Outcomes Data

Regardless of the terms one uses to describe the situation, there are compelling data in radiotherapy that link quality and safety to patient outcomes. For example, in the Trans Tasman Radiation Oncology Group (TROG) 02.02 trial for head and neck cancer Peters et al. have shown that protocol deviations are significantly correlated with overall survival. Their technique involved a reanalysis of the dosimetric data from the multicenter international trial. Similarly, a recent meta-analysis by Ohri et al. of eight trials showed that protocol deviations resulted in significantly more treatment failures and higher mortality in most cases.

Prescriptive Quality Assurance Versus Systems Thinking

In medical physics the traditional approach to addressing quality relies on prescriptive quality assurance (QA) often codified in the form of task group reports and other documents. There are numerous such recommendations (see, e.g., American Association of Physicists in Medicine (AAPM) Task Group (TG) reports listed in Appendix I ); indeed, such prescriptive QA measures form a large portion of the present book. It has been realized more recently, however, that prescriptive QA has important limitations. More than 200 steps may be required in a typical modern workflow, and prescriptive QA is ineffective at probing most of them. A more productive approach is that of “systems thinking,” which addresses the clinical care delivery process and environment as a whole. This is the subject of the rest of this chapter. Though some aspects of this may fall outside of the traditional purview of the medical physicist, it is still within the scope of practice of the medical physicist as a manager and leader of the departmental quality management program.

Safety Culture, Just Culture, and Human Error

The term “safety culture” was first used in the wake of the accident at the Chernobyl nuclear power facility. It is used to signify a “commitment to safety at all levels, from frontline providers to managers and executives” ( Agency for Healthcare Research and Quality (AHRQ) ). Safety culture has been clearly linked to patient outcomes.

AHRQ is one of the most authoritative sources on the topic of safety culture. The agency administers a patient safety culture survey each year in which thousands of hospitals participate and provides a primer on the topic ( http://psnet.ahrq.gov/primer.aspx?primerID=5 ). Four key features of a safety culture are identified:

• 1.

  Acknowledgment of the high-risk nature of an organization's activities and the determination to achieve consistently safe operations

• 2.

  A blame-free environment where individuals are able to report errors or near misses without fear of reprimand or punishment

• 3.

  Encouragement of collaboration across ranks and disciplines to seek solutions to patient safety problems

• 4.

  Organizational commitment of resources to address safety concerns

The last point especially highlights the need for leadership support of safety culture. This is a concept frequently noted in the Radiation Oncology literature as well (e.g., American Society for Radiation Oncology (ASTRO) report Safety Is No Accident). A useful discussion of the role that physicians play can be found in the editorial by Marks et al., which advocates that physicians must serve as “champions for a safety culture.” A specific example of this can be found in Potters and Kapur.

The basis of a positive safety culture is the concept of “just culture,” that is, a culture in which staff are empowered to take on safety-critical actions in an environment that supports and encourages this. To fully understand just culture and safety culture one has to appreciate what drives human error. In this regard the work of Sydney Dekker has been widely cited and influential in healthcare (e.g., The Field Guide to Understanding Human Error ). In Dr. Dekker's view the old model of error held that the major source of medical errors was the (under)performance of individual people, the “bad apples.” He calls for a more nuanced and productive approach, however, which is to understand what drives human error. The realization that “most people don't come to work to do a bad job” leads one to focus more productively on the environment and system around the person that lead him or her toward error.