Visual aid questions (VAQs) are employed widely in medical and other biological science examinations as these environments have a wealth of visually analysed material in daily practice. VAQs comprise one of the three sections of the ACEM Fellowship written examination, in which ACEM examiners assess the candidate’s competence to:
- Recognise and describe visual data encountered in Emergency Medicine practice
- Synthesise relevant and negative features of this data
- Interpret the data within a specific clinical context.
- Display knowledge consistent with safe contemporary Emergency Medicine practice in questions relating to the data.
- Consistently and adequately interpret a range of medical data in a limited time period
The ACEM format is eight questions in 80 minutes, no reading time, with a typical breakdown being two ECGs, two investigations, two radiology and two clinical images. This section has historically demonstrated lower overall pass rates by candidates than the other two written sections. (MCQs and Short Answer Questions) Several reasons contribute to this, but I believe the most important is insufficient practice (to time) of the typical range of material, leading to poor time management and answer structure when under fire on the day. In an attempt to demystify the VAQ, especially for those of you approaching the lower slopes of Mt FACEM, I’ll firstly outline how VAQs are created, then try the process with some new images, and finally list my tips to help improve your success at this domain of the quiz.
An ACEM committee of experienced FACEMs source original props from their daily work in a wide range of Australasian EDs. One will usually generate a draft question for the prop, then disseminate to the others for editing/changes/comments to create a final draft. All VAQs have the initial question “Describe and interpret”…, but less complex props will require a second question, either specific such as “Outline your further investigation”, or broader “Outline your management” to fully utilise the 10 minute timeframe. (In the most recent VAQ examination 2012.2, there were three of the eight questions with just “Describe and interpret”, and five with an additional second question.) After reaching final draft stage, that question is road tested by ACEM examiners who haven’t seen it before, and after considering their feedback, the question is finalised and banked for use in a future exam.
Let’s try this ourselves – say we wish to create an orthopaedic VAQ on the topic of knee fracture. We have three knee Xrays available and our question stem is: “A 74 year old woman is brought to your ED with a painful knee after a mechanical fall at her home. There are no other injuries, but she is unable to bear weight on it so an Xray is performed.” Decide which image is most suitable for use in the ACEM exam (that is, at a level of difficulty/complexity suitable for an emergency physician) and whether it would be “D + I” for 100% of the ten minutes, or require an additional question. I’ll put my thoughts on their merits as well as a description for each.
I think the best VAQs are those which have a visual prop complex enough to not require a second question, and which most reflect either clinically important or frequently encountered material in the ED. So I’m not keen on rarities or “spot the lesion” type props with no differentials to consider, and as an ACEM examiner, I find it easier to set pass criteria for a one part (100% D+I) question
Image 1 is an AP Xray of the left knee demonstrating a lateral tibial plateau fracture with obvious depression of the tibial plateau cortex and increased lateral tibial metaphyseal opacification. There is no obvious cortical breach or deformity, nor abnormal soft tissue features.
Image 2 is another AP Xray of the left knee; it shows an impacted distal femoral facture at the insertion site of the femoral component of a total knee replacement. The tibia is angulated laterally mildly relative to the femur and the prosthesis appears enlocated, but this requires verification with a lateral view. There is popliteal vascular calcification and the bones are osteopenic generally.
Image 3 is an AP Xray of the right knee that shows increased tibial metaphyseal opacification laterally, minimal depression of the lateral tibial plateau, and a slightly unclear cortical margin of the tibia in this area compared with the medial side. The soft tissues appear to show a displaced fat pad over the distal femur laterally which would suggest a haemarthrosis and further support the diagnosis of a relatively undisplaced lateral tibial plateau fracture.
I would choose the first and second images to use as they have more content to assess and describe, and greater clinical significance. The first would require a second question as it is an obvious fracture without xray complexity, perhaps a 50/50 time split. Either treatment or further investigation would be appropriate as a second question. Xray 2 might be OK as a 100% question. The third image on its own has subtle abnormalities that I think would be hard for the examiner to set strict pass criteria for, and which might be missed if a candidate was rushing to make up time. If used the question would be enhanced greatly by utilising this lateral view which doesn’t further demonstrate the tibial plateau fracture, but does show the associated lipohaemarthrosis. (and a fabella)
Tips for success
- Practise to time – this appears obvious but repeatedly doing VAQs to the 10 minute limit is vital. Performance will improve and gradually evolve to a concise style utilising a “dot point”/ bulleted format, with highlighting of important positive and negative elements. Don’t rewrite question or do “key points” at the start of your answer.
- Certain types of props are used in every exam, for example ECGs, so becoming adept at ECG interpretation will clearly serve you well. Similarly with common imaging (CXR, CT Brain) and investigations (ABGs and electrolytes) Many of these VAQs are completely predictable and you can be ready to nail them. ECGs lend themselves well to a template style approach, here’s an example: LITFL ECG template
- Create your own and share with colleagues – it’s also a good, fun way to study and revise topics.
- Do VAQs from previous ACEM examinations; I suggest you focus mainly on those from the last few years.
- Show your questions and answers to ACEM examiners or experienced FACEMs and listen to their feedback
- Write legibly. Write legibly. Write legibly!
- Be very careful with ABG and other calculations, its very easy to get these wrong when you’re in a hurry, so take a few extra seconds to check them twice
- At least once before the exam, do eight VAQs to time and get them marked, its very different to one or two at a time, and a real test of your technique.
- Always move on at the end of each allotted 10 minutes as its virtually impossible to make up time once you’re behind the clock. If however this still happens, put all the information you would have expanded on in your last question as a bulleted outline so the examiner will at least see the scope of your intended answer – it might still be enough for a pass! This is much better than writing an unfinished answer for the, say 6 minutes, that was all you the time you had remaining.
- The questions always ask you to “describe + interpret”, so make sure you do both – as an examiner, it continues to amaze me how many answers omit any interpretation, or a substandard one that does not contain a differential diagnosis.
- If you are asked to outline your investigations, it makes sense to structure these under headings – most candidates use bedside/blood/imaging/special or other. This is a simple way to not make simple errors like forgetting to write down obvious tests you would always perform. (eg Glucose)