So You Want to Be a Medical Physicist: Part 4 - Career Outlook

So You Want to Be a Medical Physicist
Part 4: Career Outlook

Is Medical Physics a good career to be considering?

I obviously think so, otherwise I wouldn't be writing this.  It offers a profession that allows one to make a real, tangible difference in peoples' lives for one.  It strikes a nice balance between clinical responsibility and academic inquiry.  In other words you provide clinical services, but you also get to do research.  It's challenging and stimulating.  And rarely are two days the same.

But it's not for everyone.

Medical Physics can be extremely stressful.  A Medical Physicist carries a lot of responsibility.  A single mistake can affect large cohorts of people.  The hours will be long.  I rarely leave my office at the official quitting time.  The training path is about as long as that of most physicians, but the pay is not nearly as high.

If that doesn't scare you away, maybe you should read on.

Growth in Medical Physics and Cancer Treatment Fields

No one can see into the future with perfect accuracy, but I would say that growth in the Medical Physics field is going to be rather stable and predictable for the foreseeable future, particularly if your baseline for comparison is fields in physics or even the technology sector.  My reasoning for this is the following.

1. Clinical Medical Physics is directly tied to the diagnostic testing for and the treatment of cancer with radiation.  It can deal with other diseases, but to first order, cancer runs the show in this profession.
2. Cancer incidence rates are growing despite the fact that we're getting better at preventing and treating it. This is because (a) the population is growing,  (b) less people are dying from heart disease, and (c) generally the population is getting older and the single most significant risk factor for cancer is age.  Across the world a growth rate of 3.4 %/yr across all cancers is expected up to 2030 (Bray et al. 2012).  In my province the growth rate is about 4 %/year according to the Alberta Cancer Foundation.  Conservative estimates for the USA fall around 2%/yr.
3. Nearly 2/3 of all cancer patients will receive radiation therapy during their illness (and of course nearly all of them will be imaged).  This percentage is likely to either increase or at least remain constant for several reasons including cost (radiation is relatively cheap), and its effectiveness (any new treatments that come out have to do better than that status quo before they will be adopted on a large scale).  In addition to radical or curative treatments, radiation is also very effective for palliation (symptom control/relief).
4. The clinical Medical Physics workload is not only tied to the number of cancer patients treated, but the complexity of the treatments and number of different types of treatments offered.  Across the USA there are roughly a dozen proton treatment facilities that have come online (or will soon) in the last decade or so.  We've seen a lot of growth in new techniques like stereotactic body radiotherapy (SBRT).  And even in fairly straight-forward treatments, image-guidance has recently become the standard of care.  On the horizon we have exciting developments like linac-MRI hybrid imaging-therapy units that will present a revolution in the ability to see what you're trying to treat, but will also require a lot of technical problem-solving since charged particles moving in a magnetic field and change the physics that underlie a lot of conventional practices.  All of this points to an increasing demand for Qualified Clinical Medical Physicists.

Supply and Demand

Demand

For reference, there are at present roughly 6000 Medical Physicists in the USA.  In Canada we scale down from the USA by an order of magnitude.  In my province, Alberta, there are roughly 40 of us.  These numbers have large error bars depending on definitions and what numbers you look at, but that will put you in the right ballpark to understand the approximate size of the profession.

From that size of field a few things should be apparent.  Because we're dealing with small numbers, you're not going to find a "Medical Physics" section in your local want ads.  On top of that, job vacancies are not going to be subject to a lot of fluctuation. We're dealing with low N Poisson statistics.  So if there's a particular city or cancer centre you want to work it, it could be years before a job comes available there.  In short - you have to be willing to move.

As a whole, the field is a little more predictable.

With respect to professional demand, Mills et al. (2010) assessed the profession and predicted the minimum number of new qualified Medical Physicists specializing in radiation oncology required to meet the growth rate in the field (assuming 2%/yr growth in new cancer cases over the coming decade) was 125 per year, with an ideal number at somewhere between 150 - 175.

Using a simplified "back of the envelope" calculation the American Cancer Society has estimated about 1.7 million new cancer cases will have been diagnosed in 2014 and this will be growing at a rate of somewhere between 34,000 and 68,000 more cases each year.  Between 23,000 and 45,000 of those will receive radiation.  A typical linac should handle about 300 patients per year - this means somewhere between 75 and 150 new linacs (beyond those that are being replaced) should be installed in the USA per year.  And as a rough staffing rule of thumb, you should have at least one physicist per linac.  So that's 75 - 150 new physicists per year that have to be added to the system due to growth.  That doesn't account at all for retirements (you're probably losing 20 - 30 physicists per year, if not more), nor the increasing complexity of treatments or the introduction of new and specialize treatment modalities.

If you want to expand this to North American demand, you can multiply by a factor or 1.1 to account for Canada (Mexico just doesn't appear to be on the radar yet).  These numbers also focus on radiation oncology, so you have to multiply again by 1.25 to cover the other branches of the field.  So I don't think numbers in excess of 200 new Medical Physicists needed per year are exaggerated at all.

There is one other point to consider with respect to demand.  So far, I have confined the numbers to North America.  One area where we're going to see a lot of growth in the coming decades are in developing countries, where there is not the same level of training, but the demand for cancer care is great.  For example, about a year ago Varian Medical Systems announced they had won a tender with the government of Brasil to provide 80 linear accelerators.Press Release I don't know much about the details or time frame, but that means there will be a lot of demand for qualified Medical Physicists in the coming years.

Supply

Now we come to the other side of the coin.  According to the CAMPEP Annual Graduate Program Report (2013), there are roughly 45 accredited graduate programs (34 in the US, 10 in Canada and 1 in Korea).  With regards to admissions in 2013, in total 1801 applications were reviewed, 545 offers of admission were made, and 289 students enrolled.  On the other end, 288 graduated - 162 MSc, 113 PhDs, 4 DMPs, and 9 post-PhD certificate students.  On the surface that looks like we could be training and graduating more students than the profession needs, but there are a few issues to consider...

1. According to the CAMPEP reports, roughly 15 - 25% of MSc graduates return for a PhD.
2. You also lose about 10% of graduates to "industry" - this can mean anything from staring or joining a new entrepreneurial venture to getting a job doing R&D, technical support, or technical sales with some of the big name corporations in the field.
3. Some PhDs will go into academia: 15 - 20% will go straight into post-doctoral work (although at least half of those will want a clinical position eventually).
4. Some students will not complete their programs.  CAMPEP numbers have this at 2-3%, although I can't help but wonder if this is under-reported.  Maybe my experience is just with tough programs.
5. Some students complete the program and then choose to leave the field altogether.  Or, they find that even though they can pass, they just aren't cut out for it.

When you put all of that together, it seems that the supply is roughly meeting the demand.

Unfortunately, there's a problem... residencies.

The ABR requires students to be enrolled in or have graduated from an accredited Medical Physics residency in order to write the second part of their exam.  The CCPM will require graduation from either an accredited residency or a graduate program by 2016.  There were several reasons for this.  The passing rates for the board examinations were not great, some "residency" positions may have been using residents to advance specific projects only and not properly exposing them to all dimensions of the profession, and there was no standard or independent monitoring for what a residency was supposed to cover.  Board examinations are supposed to be an independent demonstration of clinical competence, not a lone bar to get over by rolling the dice.

While introducing these new rules, was a good idea, it came with a major consequence.  There are roughly 120 accredited residency positions in North America - roughly half of what's needed.  And that's imaging and therapy residencies combined.  There are only about 60 accredited radiation therapy residencies available at last count.

For the past few years this has been creating an artificial bottleneck in the system. Competition for the available residencies is tough.  It's not difficult to see why we have MSc graduates who are desired as clinical Medical Physicists complaining that its extremely tough to compete against PhD graduates who come to the table with more research publications, and more experience in the field.  And even then graduating with a PhD doesn't guarantee one a residency.

The are, however, several initiatives underway to address this issue.

• The AAMP has instituted a residency matching program.  The will centralize the residency application process and reduce the administrative burden of running these programs.  It will also help to ensure a better match of graduates with the programs they want and avoid the stress of accepting the first offer that comes in the mail.
• There has been a lot of encouragement of "hub and spoke" models to come online that have come by way of workshops at conferences.  In such scenarios the teaching and administrative aspects of a residency would be handled by a larger academic centre, but the hands on training would come from smaller clinics that couldn't independently support a program.
• Agencies such as the AAPM and RSNA have recognized the need to fund such programs and have put over a half a million dollars towards a grant to help with funding imaging of nuclear medicine residencies.
• The AAPM officially has a student and 'trainee' (I strongly dislike that term) subcommittee now to ensure that students and residents have a direct voice on such matters.  COMP has had a student committee for several years now as well.
• CAMPEP has been working in overdrive for the past few years, accrediting programs that were previously unaccredited.  Many unaccredited programs have recently become accredited.  I don't have exact numbers, but the number of institutions offering accredited residencies has quadrupled over the last five or six years.
• If a program becomes accredited while a resident is in it, the resident will get full credit for having completed an accredited program.

Bottom Line

A career in Medical Physics is filled with all sorts of opportunities.  The growth in the field is likely to be steady, but from a student perspective, expect it to be highly competitive.  

So You Want to Be a Medical Physicist: Part 3 - How To Prepare for a Career in Medical Physics as an Undergraduate

So You Want to Be a Medical Physicist
Part 3: How to Prepare for a Career in Medical Physics as an Undergraduate

Students who are interested in clinical Medical Physics as a career commonly wonder what they can do to improve their chances of getting into accredited graduate programs, or to set themselves up for a successful entry and career into the profession.  Is there any way to get a leg up in the competition?  Are there specific elective courses that are better than others?

In my experience, there's no single "best" way to prepare yourself for graduate school or a career in Medical Physics.  And if there was, that single route would eventually become detrimental to the profession, as we all benefit from people who bring different skills and experiences to the table.  Medical Physics is largely a profession of clinical problem-solving and developing new ideas - both of which benefit from intellectual and skill set diversity.

That said, I do have some advice to offer.

Considerations for Undergraduates Interested in Medical Physics

1. Chose a program that's going to give you a solid foundation in physics.  I see a few programs out there that are oriented towards "Medical Physics" that look like they may have watered down the core physics courses or replaced them altogether with other classes that you'll end up taking again in a Medical Physics graduate program anyway.
   I have heard of graduate programs not accepting students because they don't have a strong enough physics background.  I have never heard of anyone rejected for knowing too much physics.
2. Admissions are competitive.  The average 4.0 scale GPA for admission into Medical Physics graduate programs is about 3.5 - 3.6 according to CAMPEP.
3. A high GPA is important, but not at the expense of sacrificing a good foundation.  You don't need to overload yourself (i.e. take more than a standard course load), but if you find that the only way you can get decent marks is by underloading, or by taking the bird courses (I'm looking at you Kinesiology 305: Body, Mind and Spirit), you're going to run into a load of trouble in graduate school and as a resident when you don't have the option of lightening the load.
4. Get involved with a research project.  It's great if you can do something that relates directly to Medical Physics, but don't stress yourself out if you don't have that opportunity.  The point is to get some experience working on a scientific project.  It doesn't have to be through a formal program like the NSF Research Experiences for Undergraduates program either.  A summer job in a lab counts.  A senior thesis project counts.  Volunteer positions count.
5. If at all possible, visit the graduate schools that you're most interested in and speak with faculty and graduate students and spend some time figuring out what kind of research project you would like to be working on.
6. Make sure you spend some time independently reading up on your own interests - Medical Physics-related or otherwise.  It's very easy to get burned out through classwork.
7. Like with any rewarding career, Medical Physics can be very competitive.  When plotting your undergraduate coursework, try to set up your program so that you'll have some fallback options if you don't make it into graduate school or if you decide that physics just isn't for you.  

What Electives to Take

While an undergraduate degree in physics will give you the necessary foundation in physics, a lot of students wonder about the other dimensions of Medical Physics that aren't typically covered in a physics undergraduate program.  Generally speaking the didactic coursework in an accredited program will cover everything you need to know, so you don't have to take anything outside of the regular curriculum.  But that said, here are a few recommendations of courses to fit in if you have the room (in no particular order) and that are not already part of your curriculum (which they may be).

• Biology
  Ideally you want an understanding of how DNA works, the cell cycle, respiration, and mitosis - so basically what's covered in a first year course. If you want to got a little more advanced it can help to take a cancer biology course.
  An introductory anatomy and physiology course can also help.                                                    
         
• Chemistry
  Honestly I don't know how anyone could be awarded a physics degree without a first year chemistry class, but there it is.  Organic chemistry wouldn't hurt either.
                    
• Computer Science
  Perhaps not necessarily a course, but it's important to learn to program well in at least one language. Lot's Medical Physics research involves coding.  It would help to be familiar with Monte Carlo methods and simulations.  It also really helps to have a strong understanding of computer networks.
                            
• Engineering
  If you can swing it, try to get into a signal or image processing course.
  An introduction to process engineering (failure modes effects analysis etc.) wouldn't hurt.    
                                                         
• Humanities
  Learn to write well.  People underestimate how important a skill writing is.                      
                     
• Mathematics
  I would assume that a physics degree would cover a basic calculus sequence, differential equations, linear algebra, and include a mathematical methods for physicists course.  If your program doesn't get you to this level through core courses, take them as electives.  To do any imaging work you need to know what a Fourier Transform is.
  On top of that I might also recommend a statistics or biostatistics course.                    
                         
• Neuroscience/Psychology
  If you're interested in this kind of thing - particularly if you want to any MRI work, it would help to take at least introductory courses here.                                                                
                                
• Physics Options You Should Take
• A senior laboratory class with error analysis methods
• Computational physics or numerical methods
• Electronics and/or digital circuits
• Introductory Medical Physics course (if available)                                                                     

Things to Look For in a Graduate Medical Physics Program

Choosing the graduate program that's right for you can be a tough choice.  There are roughly 35 accredited graduate programs out there and countless other non-accredited ones.  Unlike with schools themselves there is no Medical Physics graduate school ranking that I'm aware of.  Nor should there be.  Numbers can carry more authority than we sometimes intend.  When you rank schools according to a set of criteria, those rankings are only relevant to the extent that the criteria reflect what's important to the student.

What matters most in graduate school is what you get out of the experience.  It matters what you learn.  It matters what skills you acquire.  It matters what results you produce.  And it matters what networking connections you make.  The different schools have different strong and weak points so it's important to make choice based on your goals, personality and interests in a manner that's going to set you up for success.

One thing that does matter to almost everyone considering a career in Medical Physics right now is CAMPEP accreditation.  You need this to get certification, and while you can still work as a Medical Physicist without certification, that's going to be an uphill battle.

After that, you really have to figure out what's most important to you.  Here are some factors to consider (again in no particular order) that might help you to do that.

• Access to modern equipment and facilities.
Is the program affiliated with a hospital? What imaging an treatment modalities are available there?  Has anything new been installed recently?  Does the program have access to a PET or PET/CT machine for example?  An MRI machine?  Does the facility perform any form of stereotactic radiotherapy?

• Hands-on experience with that equipment.
Most students won't get to use hospital equipment freely, but are you going to get through the program without ever having touched a linac?

• An empahsis on the physics of medical physics compared to rote regurgitation of the didactic material.  Technology in medical physics changes quickly.  The physics doesn't change that much. (Flags to look for might include lower admission standards compared to other programs [don't require a physics degree], students who tell you the course work is easy compared to undergrad, minimal research done by faculty, etc.)

• Opportunities to do QA work.
This will (i) give practical, relevant experience, (ii) give insight into the work involved with being a clinical Medical Physicist, and (iii) help to pay some of the bills.

• Research interests of the faculty.
Even if you are more oriented towards clinical work than research, you'll be doing some kind of project for your graduate work and as a clinician, you'll be bringing new technology into the clinic on a regular basis and constantly challenged by problems for which there is no readily available answer.  Look at the current projects being done in the department.  Look at how much funding the faculty has and for which projects.  How closely does what's being done align with your own interests?

• Another dimension of research that can be easily overlooked is commercialization opportunities.  Over the years there have been lots of start-up companies that have come out of medical physics research.  Not everyone is interested in such things, but if I was a student today I would certainly factor this in.

• Faculty dedicated teaching time.
When you talk to current students in the program, do they have regular meeting times with their supervisors? Are they happy with the quality of the lectures? Or are the faculty impossible to pin down due to clinical committments?

• Where the graduates end up?
Most accredited medical physics programs now publish such information online. Are the graduates getting residencies? Are they going places you could see yourself going?

• Cost and financial support.
Not all programs cost the same.  Not all guarantee financial support or opportunities for QA work or TA/RA positions.  Also factor in cost of living.

• Quality of extra-curricular life.
It's important to weigh in all the other stuff too (available activities, sport, groups, city life, commute times, weather, will your partner be happy there, etc.)  You don't want to be miserable in your down time.

If at all possible visit the schools on the top of your list and talk with faculty and current graduate students.  This can help you get the answers to the above questions and any of your own, and give you a feel for the atmosphere you'll be plunging into head first.  Are the current students happy?  Do they get to attend conferences?  Are there particular faculty members that might fit well with your learning style, or vice versa?  A visit also gives you advantages in the competitive admissions process.  It's a tangible demonstration of interest in the specific program.  It will help you to tailor your application to the specific school and program.  And, it puts a face to your name.

All of this assumes that you have a choice.  You have a choice of where to apply of course.  But ultimately, you're limited to where you're admitted.  And we're only talking about a couple hundred positions in total across North America.  Admissions are competitive.

That said, you may find yourself with a choice and for some, a choice between two good options can be agonizing.  If you're stuck in this position, it's best to keep in mind that sometimes there is no identifiable single optimum.  Sometimes you have multiple good options that are on par with each other.  I can't offer any better algorithm for figuring out the way to go in such circumstances.

Sometimes, you just have to make a decision.

So You Want to Be a Medical Physicist: Part 2- Becoming a Medical Physicist

So You Want to Be a Medical Physicist
Part 2 - Becoming a Medical Physicist

It's not uncommon for physics students to check out Medical Physics at some point during their studies.  Sure, Medical Physics may not be as sexy as working on wormholes in space-time.  But the prospects of working through a PhD to become a thirty-something jumping from post-doc to post-doc for years, all for perhaps a 1 in 10 shot at landing an academic position, can loom like dark clouds over the "purist" physicist.  And Medical Physics is ever-present, hovering in that no-man's land between academia and "industry," with the promise of a well-paying career that will make a difference in people's lives.

About the time I realized I wasn't going to be the one to derive the secret formula for a real-life warp drive engine, I began to look at Medical Physics as a potential career.

Here, I'll try to give an overview of how one can become a clinical Medical Physicist.

I'll start at the end point, with the term Qualified Medical Physicist.  What that usually refers to is a clinical Medical Physicist who has obtained a recognized certification of clinical competence.  That certification has more-or-less become the gateway that one has to get through in order to work as a Medical Physicist.  This certification is given by a number of internationally recognized bodies.  In North America these bodies are:

• Canadian College of Physicists in Medicine (CCPM)
• American Board of Radiology (ABR)
• American Board of Medical Physics (ABMP - no longer active)

Technically speaking there are only a handful of states that legally restrict the practice of medical physics to state-licensed Medical Physicists.  In most other places in North America, to work as a Medical Physicist, board certification is not technically mandated.  But don't let that allow you to brush off it's importance.  Any person considering a career in Medical Physics, you should really treat board certification as a mandatory career step because:
 (a) in any job competition those with certification are chosen over those without it,
 (b) general trends in all healthcare fields are moving towards increased regulation, and
 (c) preparing for certification actually does make you more competent in the clinic.

In order to get to board certification, the post-secondary education and training route typically looks something like this:

1. Undergraduate Degree in Physics (or a closely related field)
   Your undergraduate degree should provide you with a solid foundation in physics.  Medical Physics is very much an applied physics field, and in many ways a lot closer to engineering than some other branches of physics.  Closely-related fields include engineering physics, nuclear engineering, physical chemistry, biomedical engineering and some (but not all) undergraduate programs that focus speficially on medical or health physics.  Competitive GPAs for entry into most graduate programs are in the ballpark of 3.5 on the 4.0 scale.                
2. Graduate Degree in Medical Physics
   Graduate programs in Medical Physics combine (in different ways) roughly one year of didactic courses that you need to cover to be competent in the field, and a research project, and differing degrees of hands-on experience.  At minimum you require a master's degree for certification, however due to the competition for residencies a PhD is often the status quo.  It's not uncommon for students to get the MSc first, attempt to get a residency and return for the PhD if unsuccessful.  Just as in other branches of physics, the PhD has a much larger research project that is expected to be novel.
   
   Program accreditation is critical.  CAMPEP, the Commission on Accreditation of Medical Physics Education Programs, is a commission set up to ensure consistent quality of education in Medical Physics graduate programs and residencies, and they maintain a list of accredited graduate programs.  By 2016, the CCPM will require that applicants for membership have completed either an accredited graduate program or an accredited residency.  In order to write part 1 of the ABR Medical Physics exam, candidates will need to be enrolled in or have graduated from an accredited medical physics program.                                                                                                                    
3. Medical Physics Residency
   A residency is a 2-3 year position where the resident moves through various clinical rosters (in radiation oncology these would include: machine QA, commissioning, treatment planning, CT simulation, brachytherapy, special techniques, etc.) while working under the supervision of a Qualified Medical Physicist.  It is also common for residents to be expected to make substantial contributions to clinical or research projects (which is why the PhD is often preferred for these positions).  Again the CCPM will require either the graduate program or the residency to be accredited.  In order to write part 2 of the ABR medical physics exam, you need to have completed an accredited residency.                                                                                                  
4. Other Options - DMP Programs
   Another option for students coming out of undergrad are the Doctor of Medical Physics (DMP) programs, which roughly combine an MSc with a residency over four years.  These are fully accredited programs and offer the guarantee of a residency.  My understanding, however, is that the student pays for the residency component, where I personally feel that residents need to be reimbursed for the valuable work they do for a Medical Physics Department.
   Side note: I believe there is currently only one of these programs that is accredited.                              
5. Other Options - Physics PhDs from Other Fields
   There are also options available for those who have PhDs in other branches of physics who are interested in a professional career in Medical Physics without completing a second PhD.  The first, is obviously to do an accredited two-year MSc.  In my experience a person with a PhD in a different field and and MSc in Medical Physics is seen as equivalent to a candidate with a PhD in Medical Physics in terms of competing for jobs (all other factors being equal).
   
   Another option is a post-PhD certificate program (see accredited graduate programs, or University of Calgary ROP), which can be completed in under a year.  These essentially allow the PhD to complete the didactic coursework in Medical Physics and are treated as equivalent to having completed a graduate degree in medical physics.

It's probably worth mentioning that if you live in Ontario they may use a slightly different system that relies on a peer review examination that occurs at the end of a residency.  CCPM membership is generally accepted on par there however.

For details about how the training process works in other parts of the world, I would recommend:

• Institute of Physics and Engineering in Medicine (UK)
• Australasian College of Physical Scientists and Engineers in Medicine
• European Federation of Organisations for Medical Physics
• International Medical Physics Certification Board
• International Organisation of Medical Physics

So You Want to Be a Medical Physicist: Part 1 - What Exactly Is a Medical Physicist

So You Want to Be a Medical Physicist
Part 1 - What Exactly Is a Medical Physicist?

Medical Physics can provide rewarding and stimulating profession, but there can sometimes be a lot of mystery behind what a Medical Physicist does and confusion about the process of getting into it.  I am a senior medical physicist working, teaching, and doing research in Alberta, Canada.  In this and subsequent documents I hope to offer some helpful insight based on my own experience to students or recent graduates curious about Medical Physics careers.

Medical Physics

In its broadest scope, Medical Physics is the branch of physics that applies to solving problems in medicine - problems regarding how various forms of electromagnetic and particulate radiation interact with the human body, development of imaging devices, optimization theory, modeling biological responses to treatment or disease kinetics, etc. are all examples.  In that sense, there is actually a lot of research in physics and in engineering, mathematics, chemistry and biology that could qualify as "Medical Physics."

With that said, throughout this post I'll largely be focusing on clinical Medical Physics though.  By that I mean the practice of physics in the provision of clinical services as a profession.

Radiation Oncology Physicists

Roughly 80% of Medical Physicists work in the field of radiation oncology - the application of radiation to the treatment of cancer (and a few other types of diseases).  This work has many dimensions, which is why sometimes it can be difficult to get a straight answer on what a Medical Physicist does.  It's important to underscore that although patients may not frequently see a Medical Physicist as often as they would a physician or a nurse, nearly all the work a Medical Physicist does has a direct impact on patient care.  Broadly speaking, the work of a clinical radiation oncology physicist involves:

• establishing, supervising and executing a quality assurance program for the devices used to deliver radiation and their supporting systems (linear accelerators, brachytherapy afterloaders, image guidance systems, proton or heavy ion accelerators, CT simulators, MRI simulators, etc.)
• commissioning of new radiation treatment devices, facilities and their supporting systems as they are introduced into clinics
• administration of the computer networks and software used to run the radiation delivery machines and generate treatment plans
• responsibility for the integrity of radiation therapy treatment plans (which can take the form of plan checking, consulting on difficult, abnormal or new modality plans, and in some cases planning treatments)
• developing and updating procedures for radiation therapy treatment, and providing technical guidance for administrative decisions
• investigating clinical problems (everything from calculating the dosimetric consequences of a treatment error to computer network slowness to chasing down the source of an asymmetry in a treatment beam)
• leading clinical investigations or projects (examples include measuring how accurate your treatment planning system is at calculating dose in the presence of prosthetic hips, or investigating the clinical consequences of delivering radiation at a faster dose rate)

Diagnostic Imaging, MRI, and Nuclear Medicine

The other roughly 20% of Clinical Medical Physicists work in diagnostic imaging, MRI (MRI is it's own specialty), and nuclear medicine.  I won't go into as much detail with respect to these sub-specialties, but conceptually much of the work is similar and again, has a direct impact on patient care.  These sub-disciplines involve commissioning new imaging devices, establishing and maintaining quality assurance testing, network administration, clinical problem solving, consulting, administration and clinical research.  In the imaging specialties the focus of the commissioning and quality assurance work is to provide the optimum image quality for the best possible diagnoses, while balancing that with the safe delivery of radiation and minimizing unnecessary exposure.

Radiation Safety

Medical Physicists (from all disciplines) often also function as radiation safety officers (RSOs) - dealing with the occupational issues involved with the safe delivery of radiation.  This can involve personal dose monitoring, supervising a radiation safety program, teaching, and dealing with all of the licensing (applications, record-keeping, inspections, follow-up actions) involved with operating devices the deliver ionizing radiation.  I should note however that RSOs are not always Medical Physicists.  There is an entire sub-field called health physics that deals specifically with radiation safety.  Because of the cross-over between the fields, it's not uncommon to see Medical Physicists in these roles.

Academics (Teaching and Research)

In addition to clinical duties, many Medical Physicists also have academic appointments at universities and therefore are involved in both teaching and research.  I don't have exact breakdowns, but academic appointments appear to be more common in Canada than in the USA.  In the USA, there are more small and independent facilities.  Roughly one fifth of American Medical Physicists are solo practitioners and in such circumstances, academic responsibilities are unlikely.  In Canada, cancer centers are all publicly funded and tend to be larger facilities associated with universities, and as such have a mandate to conduct research.  According to a recent COMP survey, roughly a quarter of Canadian Medical Physicists' time is, when averaged out, spent on teaching and research combined (the standard deviation is quite wide in my experience).

Teaching duties can involve instructing medical physics graduate students, medical physics residents, undergraduate physics students, radiation oncology residents, radiation therapy students, medical students and many others.  These can be through formal university courses, laboratories, or semi-formal teaching situations such as in-services.

Medical Physics research is difficult to summarize because there are a very large number of problems in medicine that draw on physics to solve.  If you want to get a real idea of what current research involves I would recommend reading the following journals:

• Medical Physics
• Physics in Medicine and Biology
• Journal of Applied Clinical Medical Physics
• Red Journal (International Journal of Radiation Oncology, Biology, Physics)
• Green Journal (Radiotherapy and Oncology)
• International Journal of Radiation Biology
• Radiation Research

There are a lot of other very good journals in the field, and if you're serious about exploring research in Medical Physics, I suggest starting with one of these and following your nose.  If you are an undergraduate student, your library should have a subscription to these journals.  If not, many of them provide open access to the more popular articles - editor's choices, or award winners.  Another very good resource that I use to help keep on top of research in the community is Medical Physics Web. This site provides layperson-friendly summaries of recent publications in the fields along with author interviews that can help one learn about the field, which can be especially helpful as you learn a lot of the technical jargon.

Where to Find More Information

• American Association of Physicists in Medicine (AAPM)
• Canadian Organization of Medical Physicists (COMP)
• International Organization for Medical Physics
• Institute of Physics and Engineering in Medicine (IPEM)
• European Federation of Organisations For Medical Physics (EFOMP)
• Australasian College of Physical Scientists & Engineers in Medicine (ACPSEM)