SBA Question Technique: How to Approach Single Best Answer Questions
Master the SBA format used in both UKMLA and PLAB 1. Learn how to eliminate distractors, handle uncertainty, and avoid the most common mistakes medical students make.
Single best answer (SBA) questions are the format used in both the UKMLA AKT and PLAB 1. Unlike true/false or extended matching questions, SBAs require you to select the single most appropriate answer from five options — even when multiple answers appear plausible. Mastering the SBA format is as important as knowing the clinical content.
Read the Question Stem Carefully
The question stem contains all the information you need to answer correctly. Read it in full before looking at the answer options. Pay close attention to the patient's age, sex, presenting complaint, examination findings, and investigation results — each detail is there for a reason. The final sentence (the "lead-in") tells you exactly what is being asked: most likely diagnosis, most appropriate next investigation, most appropriate management, etc.
Eliminate Distractors Systematically
SBA questions are designed with four distractors — plausible but incorrect options. A systematic elimination approach is more reliable than trying to identify the correct answer directly. First, eliminate options that are clearly wrong. Then, from the remaining options, identify the one that is most appropriate given the specific clinical scenario described. "Most appropriate" often means the safest, most evidence-based, or most immediately actionable option.
Handling Uncertainty
There is no negative marking in either the UKMLA AKT or PLAB 1, so always answer every question. If you are uncertain, eliminate as many distractors as possible and make an educated guess from the remaining options. Do not spend more than 90 seconds on any single question — flag it and return at the end if time permits.
Common Traps
The most common SBA trap is selecting the "textbook" answer rather than the answer that fits the specific scenario. For example, the first-line investigation for chest pain in a 65-year-old with risk factors is an ECG — not a troponin, even though troponin is more sensitive for MI. Another common trap is selecting a management option that is correct in general but inappropriate for the specific patient described (e.g. a drug that is contraindicated in pregnancy or renal failure).