Are Physics Assistants a Bad Idea? A response to the Med. Phys. 43 (1) Point/Counterpoint, “Medical physicist assistants are a bad idea”

Silvia Neuteboom

The Ottawa Hospital Cancer Center

In the January 2016 edition of Medical Physics, Dr. Doracy P. Fontenla of Memorial Sloane Kettering Cancer Center, and Dr. Gary A. Ezzell of the Mayo Clinic Arizona argue the Point/Counterpoint proposition, “Medical physicist assistants are a bad idea.”  Although the authors are discussing the American medical physics milieu, this is an interesting topic for the Canadian medical physics community as well.

In Canada, large centers do employ physics associates (who are sometimes called assistants or technologists or other titles) to handle some of the medical physics workload. Most commonly, associates are tasked with the ‘heavy lifting’ of bulk, routine QA measurement. For example, at The Ottawa Hospital Cancer Center, where I work, physics technologists do  50+ patient DQA measurements per week in support of the Tomotherapy and VMAT treatments, and another  80 machine QA test lists, each consisting of on average 6-8 test items,  weekly.  This type of work is referred to by Dr. Fontenla as belonging more properly to a junior medical physicist position; however, after the learning curve is over, a fully qualified medical physicist would find these tasks not only unchallenging but career-stifling.  Therefore, as Dr. Ezzell points out, to ensure that the professional abilities of a qualified medical physicist are valued, as well as utilized to their full capacity, physics associates are necessary.

The concern is raised by Dr. Fontenla that the use of MPAs in the US will erode the availability of physicist jobs. A brief perusal  of Internet job listings for ‘medical physics’  tells a different story:  of 14 listings found on on a given day, for example, 7 were for medical physicists, 3 were for medical physicist assistants, and 4 were for other positions in the medical physics world.  On the AAPM website, the job listings show not a single one for MPAs.  Here in Canada, at the time of writing this article, there was currently 1 listing for a physics assistant with the BC Cancer Agency, 3 listings on the COMP website for full time medical physicists, and 1 for a residency.  By the numbers alone, medical physicist vacancies remain in the majority, which indicates that the need for qualified medical physicists is not disappearing under a wave of poorly qualified MPAs hired by overly budget-conscious hospital administrators.  

Both authors make the point, although approaching it from different sides, that the key to whether medical physicist assistants are a good idea or not lies in their training and qualifications. Another quick perusal of the US want ads shows no consistency around the issue of qualifications – of the 3 MPA vacancies  advertised, all 3 had different educational requirements, ranging from ‘not specified’ to a Masters in Medical Physics. All 3 also list different duties in the job description. It seems that at present, there is no ‘one size fits all’ scenario. In reality, the education and training needed to do a physics associate’s job is going to depend greatly upon what the job entails. For a PA who will be performing only routine QA measurements, perhaps a B.Sc. in Physics or Engineering is sufficient, but an employee who will be acting as a QC coordinator or even as a research assistant or computer programmer may need a Masters, or qualifications from outside the world of medical physics, such as a computer science degree, Lean certification, or even an engineering degree. Even with such qualifications as prerequisites, any candidate lacking prior medical physics experience who is hired to be a PA will obviously also require extensive on-the-job training, as linacs, Tomotherapy machines, and Cyberknifes are still not common instructional materials  in the average Canadian university.  Even those with prior medical physics experience will  need to be oriented to the equipment, policies, and procedures of the new workplace.

The key, then, to ensuring that physics associates are a ‘good idea’, lies in the training and supervision provided by the hiring department. As Dr. Ezzell points out, PAs must work under the supervision of qualified medical physicists. However, an experienced PA can – and should be allowed to – perform the job with minimal oversight;  it makes no sense for the physicist to micromanage an employee who, by dint of years of practical, hands-on experience, may in fact be more familiar with the process than the physicist themselves. Having a PA who is a mere ‘button-pusher’ is also not sufficient, for in the radiation therapy department, button-pushing without understanding is a source of disaster. Thus the preferred role for the physicist to play here is not not only supervising, but imparting knowledge, so that the PA may become a useful support to the physicist and to the department as a whole. To get a PA to this point requires a complex mix of both formal and on-the-job training, judiciously supplemented by outside courses and other career-development opportunities.  

The medical physics department that chooses to invest in their staff in this way wins many benefits. To start with, an enormous burden of profoundly routine work is shifted off the shoulders of the physicist, freeing him to do what a Ph.D. must do best: think. In this time of increasing technological complexity, almost every clinical challenge that cross a physicist’ desk requires a thoughtful and unhurried approach to finding a solution. As we all know, the modern healthcare environment does support thoughtful and unhurried approaches; therefore anything that can enable them should be welcomed.

Likewise, when she knows a capable and trained person can be trusted to perform essential tasks (such as QA) to a high standard, the burden of worry is also lifted from the physicist’s mind.  A rock-solid QA program, staffed by knowledgeable PAs, provides a steady stream of reliable data on machine performance, which the physicist can then utilize without undue concern. On the other hand, a QA program staffed with a constantly revolving cast of temporary data collectors, such as students and residents, will always suffer the vicissitudes of repeated cycles through the learning curve and will always have question marks hanging over the data produced thereby.

It also seems obvious that there is inherent waste in asking a clinical professional like medical physicists to invest considerable amounts of their time in the mundane day-to-day operational decisions and chores of the department. Things like inventory upkeep and equipment repair, radioactive source shipping, reading in-vivo dosimeters, and computer coding are better done by other staff.  It is the role of a physicist to innovate; how can innovation occur when said physicist is, for example, off in the source room peeling trefoil labels from an empty bucket of HDR sources?

The final bogeyman raised by Dr. Fontenla in Point/Counterpoint is that having less-qualified individuals perform certain tasks can be dangerous. Dr. Ezzell counters this by pointing out that he can find no evidence in the literature cited that supports this view. To this I would add, out of my own experience, the assertion that well-educated physics associates, who know what to look for, can serve as yet another set of eyes on the lookout to protect the patient from adverse occurrences. 

Even without the benefit of a Ph.D., a residency, or CCPM certification, physics associates in Canada know, understand, and take seriously their duty to provide patients with the safest, most efficient, best possible care. That includes knowing when it is time to step back and defer to the professional judgement of the physicist. PAs, sensibly, will not overstep the bounds of professional practise that govern medical physics or take upon themselves judgments they should not.  Now, the onus, the challenge, is on the medical physicist to recognize in turn, the capabilities and possibilities offered by good physics associates.

In conclusion, then, the question to be asked is not whether PAs are a good idea, but,  how do we, the medical physics community, ensure that our job, our one job of caring for patients, is done excellently? The answer lies not in a ‘circling of the wagons’ around the profession of medical physicist; but in fully engaging all possible resources, including physics associates, in the task at hand.  

— Silvia Neuteboom, B.Sc. is a Physics Technologist employed at The Ottawa Hospital Cancer Center since 1999. She is the former Chair of Medical Physics Associates of Canada ( and continues to advocate for the professional advancement of PAs.

— This Article was published in InterACTIONs (62(2) April/Avril 2016). The permission has been given by InterACTIONs to OMPAC to post it on

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