Examiner tips for the CR1 Physics exam
Article by: Dr Gaurav Sundar
From answering every statement to spending time with radiographers, chief examiner Dr Gaurav Sundar shares practical insights to help candidates excel in the CR1 Physics exam.
Preparing for the exam
Starting radiology training is an exciting time, but before long many of you will begin thinking about the FRCR Part 1 exams. For many residents, physics is the part that causes the greatest anxiety. Unlike anatomy, physics is often something that many of us have not studied since starting medical school. It is therefore understandable that residents approach the exam with a degree of apprehension.
The good news is that the exam is not designed to catch you out. As chief examiner, one of the questions I am asked most often is, ‘What's the best way to prepare?’. Although everyone has their own preferred way of studying, there are a few common themes that I have seen among candidates who perform well.
Start early and focus on understanding concepts
Physics is much easier to learn gradually than to cram into the final few weeks before the exam. Many topics build on one another, so giving yourself time to revisit concepts and reinforce your understanding makes a real difference.
Try to focus on understanding concepts rather than memorising facts. While there are a few facts and figures that require memorising, much of the exam is designed to test your understanding of the principles behind medical imaging. One of the most common mistakes candidates make is trying to memorise facts without understanding why they are true.
When revising, regularly ask yourself, ‘Why is this the answer?’ rather than simply ‘What is the answer?’. If you understand how X-rays are produced, why MRI contrast changes with sequence parameters or how ultrasound images are generated, you will often be able to answer questions that you have never seen before. The exam deliberately tests understanding rather than simple recall.
Spend time with the radiographers
One of the most understated and useful sources of learning is not in the lecture room or the revision textbooks but something far friendlier and accessible to everyone – the radiographers in your own department. It is worth remembering that the physics you are learning is directly relevant to your everyday work as a radiologist. When reporting a CT scan, think about why windowing changes the image. Ask the CT radiographer, ‘What is the purpose of the topogram when acquiring the CT?’. When scanning with ultrasound, consider why changing the frequency alters penetration and resolution. Ask the sonographer, ‘Why do you change the scale when performing a duplex examination?’. When reviewing an MRI, think about why different tissues appear bright or dark on different sequences. Ask the MR radiographer to show you the different protocols used in your department for various clinical indications. ‘Why did you use that specific fat suppression technique for this study and not the previous one?’. When performing a fluoroscopy list, consider how you can reduce radiation to yourself and other staff in the area by using pulsed fluoroscopy or collimation. Ask the radiographer, ‘How does increasing the kVp or reducing mA affect the skin dose?’.
Connecting physics to your everyday work makes revision far easier and much more memorable.
The exam
The exam itself consists of 40 true/false questions, each containing five individual statements. There is no negative marking, so every statement should be answered. Candidates sometimes lose marks not because they lack knowledge, but because they read a statement too quickly or miss an important qualifying word such as ‘most, ‘least’, ‘always’ or ‘only’. Taking a few extra seconds to read each statement carefully can make a surprising difference.
One piece of advice I often give is not to overthink the questions. Candidates sometimes assume there must be a hidden trick. In reality, our aim is to write questions that are fair and that assess your understanding of the curriculum. Read exactly what is written and avoid adding assumptions that are not there.
Practice questions are invaluable, but they are most useful when you learn from your mistakes. If you answer a question incorrectly, spend a few minutes understanding why rather than simply memorising the correct answer. Those lessons are usually the ones you remember on the day of the exam.
Finally, remember that the goal is not simply to pass an exam. A good understanding of imaging physics will help you throughout your career. It will allow you to optimise image quality, minimise radiation dose, recognise imaging artefacts and choose the most appropriate investigation for your patients. The knowledge you gain now will continue to be useful long after the exam is over.
Many residents begin their revision convinced that physics will be their biggest challenge, yet every year many of them pass comfortably. With steady preparation, a good understanding of the underlying concepts and plenty of practice, there is every reason to approach the exam with confidence.
I wish you every success with your preparation, and I hope to congratulate many of you as successful FRCR candidates in the near future.