Case questions are where well-prepared candidates lose marks they should have kept. The knowledge is there, but the vignette is long, the patient has six medications and four lab values, and the clock is running. Reading from the top and hoping the answer appears is the slowest way through. A fixed method is faster, and it is something you can practise until it is automatic.

This article sets out a five-pass method for reading any clinical case on the PEBC Qualifying Exam Part 1, the traps case writers rely on, and how to practise so the method holds up under time pressure.

Why case questions feel harder than they are

A single-fact question asks you to recall one thing. A case asks you to decide which of twenty things matters. That is a different skill, and it is the one a pharmacist uses at the counter every day: a patient arrives with a history, a medication list and a new problem, and most of what they tell you is not relevant to the decision in front of you.

The difficulty is rarely the pharmacology. It is the sorting. Candidates who struggle with cases usually know the drug facts and lose time in three places:

• Reading everything with equal attention. The vignette is written so that only a few details decide the answer. Treating all of them as important is how four minutes disappear.
• Reading before knowing the question. Without the question, you cannot tell which details are decisive, so you read the case twice.
• Letting the options do the thinking. Four plausible answers will each pull you toward a different part of the case. If you have not formed your own answer first, you are choosing between someone else's ideas.

The five-pass method

Five short passes, always in the same order. With practice the whole sequence takes well under a minute.

1. Read the question first

Go to the last line before the options. "Which of the following is the most appropriate recommendation?" tells you to look for a problem and a fix. "Which medication is most likely responsible?" tells you to look for a new symptom and a timeline. You now know what you are hunting for.

2. Sort the patient

Before any drug, fix the person in your mind: age, sex, pregnancy or breastfeeding, weight if it is given, kidney function, liver function and allergies. These are the modifiers that turn a correct drug into a wrong answer. If the case mentions any of them, it is almost never decoration.

3. Match every drug to a reason

Run down the medication list and pair each drug with a condition in the history. Two things fall out of this step on their own: a drug with no indication, and a condition with no treatment. Either one is often the whole question.

4. Find what changed

Cases are built around a change: a drug started last week, a dose increased, a new symptom, a lab value that moved. Look for time words such as "three days ago", "since starting" and "recently". The change and the timeline usually point straight at the answer.

5. Answer before you look

Decide what you would recommend, in your own words, and only then read the options. If your answer is there, choose it and move on. If it is not, the options tell you which part of the case you misjudged, and you re-read only that part.

Reading the numbers

Lab values and vital signs are in a case for one of three reasons. Decide which one applies and you know what to do with the number.

• It changes the dose or the drug. Kidney function is the usual example. If a creatinine clearance or eGFR is given, check every renally cleared drug on the list against it before anything else.
• It is the adverse effect. A potassium, sodium, INR, creatinine or liver enzyme that has moved since a drug was started is the clue to which drug is responsible.
• It shows whether treatment is working. A blood pressure, A1C or lipid result tells you whether the patient is at target, and so whether the next step is to intensify, continue or reduce.

Values that are normal are still information. A normal potassium rules out the answer that depends on it being abnormal. Use normal results to eliminate options rather than skimming past them.

Check the units. Canadian cases report glucose, lipids and creatinine in SI units, and a number that looks alarming in one system can be unremarkable in the other.

Linked questions on one patient

Some cases carry several questions about the same patient. They reward a slightly different approach.

• Invest in the first read. You will use the patient details several times, so the sorting in passes 2 and 3 pays for itself.
• Treat each question on its own. A later question does not depend on your answer to an earlier one. If you were unsure about the first, do not carry that uncertainty forward.
• Watch for new information. A later question may add a result, a new symptom or a change in the plan. Read its opening line carefully: the patient you sorted a minute ago may have changed.
• Do not let one hard question cost the set. If one of the linked questions is beyond you, make your best choice, flag it, and collect the others.

Six traps case writers use

1. The vivid irrelevant detail. An occupation, a recent trip or a family history that has nothing to do with the question. If it does not connect to what is being asked, let it go.
2. The drug without an indication. A medication on the list that matches nothing in the history. It is there to be noticed, either as the cause of the problem or as the thing to stop.
3. The untreated condition. A diagnosis in the history with no therapy against it. The question may be asking what is missing rather than what is wrong.
4. The product the patient bought themselves. A non-prescription medicine, a natural health product or a supplement mentioned in passing is a common home for the interaction.
5. The answer that is true but does not answer the question. An option can be a correct statement about the drug and still not be the most appropriate action for this patient.
6. The right drug for a different patient. First-line therapy for the condition, made wrong by this patient's pregnancy, kidney function, allergy or age. This is why pass 2 comes before pass 3.

How to practise cases

The method only helps if it runs without thought, and that takes repetition.

• Practise the passes out loud at first. Say "question, patient, drugs, change, answer" as you go. It feels slow for a week and then it disappears into habit.
• Time the case, not just the question. A case with three linked questions deserves more time on the first read and less on each question. Learn what that balance feels like.
• Review your reasoning, not your letter. When you get a case right, check that you were right for the reason in the explanation. A correct guess on a case is a wrong answer waiting for exam day.
• Log the pass that failed. When you get one wrong, write down which pass let you down: missed the question, missed a patient modifier, missed the change. Your errors will cluster, and the cluster tells you what to practise.
• Mix the topics. On the exam you will not know that the next case is about heart failure. Practise cases in mixed sets so recognising the topic is part of the exercise.