Stepping into a NAC-OSCE station is like stepping into an alternate reality because at the end of the day, it is one. There, many common daily clinical practices are suspended and replaced by new rules of engagement. One of these new rules is particularly challenging to follow: only ask the simulated patient (SP) one question at a time.

Why is it such a challenging rule to follow? No one enjoys conducting conversations in a rigid, robotic, interrogatory form. We all prefer more natural, flowing, open conversations. For this reason, paired or sets of stacked questions often slip into our conversations to produce a more conversational, varied, and relaxed tone. But in the alternate reality of the NAC-OSCE, these types of questions will compromise the accuracy of the information you gather from the SP. Remember the SP may only answer one question at a time.

So, how can you avoid pairing and stacking your questions? Not to worry, I'll break it down here and show you how to recognise and avoid them altogether.

On Paired Questions

Paired questions occur when we ask a question that couples, that links two symptoms together with a conjunction like 'and' or 'or'.

For example:

- "Do you have any nausea or vomiting?"

- "Do you have any fever or chills?"

- "Any changes in your vision and hearing?

- Have you noticed any dizziness or have you fainted?

Paired questions elicit a reply of "yes" or "no" from your SP, directly resulting in an undefined, unspecified answer. Which associated symptom is the SP referring to if they answered in the affirmative? Are they experiencing the nausea or are they experiencing the vomiting? Maybe they are experiencing both?

If you catch yourself asking a paired question, you'll have to clarify and rephrase your questions thereby losing precious exam time.

How can you avoid asking paired questions?  First, recognise that you're asking paired questions. Second, practice isolating all the symptoms in your HPI into single questions. Lastly, practice makes progress.

On Stacked Questions

Stacked questions, also known as layered questions occur when we ask multiple questions in rapid sequence. In other words, one question is quickly followed by many others. This causes confusion for the SP as they aren't sure which question to respond to first, knowing that they can only reply to one question at a time.

Here are some examples:

- "How have you been coping with the lack of sleep? Do you find you have less energy? Are you waking up tired?"

- "How would you describe your back pain? Would you say it's a sharp pain? Does the pain radiate anywhere else in your body? Do you have any stiffness?"

- "Have you noticed any changes in your skin lately? Any dryness? Any new hair growth? Has anyone said that you look pale lately?"

From these examples, you can see how the questions are stacked and how it would be quite challenging for the SP to know where to start in answering them. Similar to the paired questions, stacked questions elicit a reply of "yes" or "no" from your SP, directly resulting in an undefined, unspecified answer. Are they answering the first question? Are they answering the second or last question?

If you catch yourself asking stacked questions, you will have to ask your questions again, separately, thereby losing precious exam time.

How can you avoid asking stacked or layered questions?  First, recognise that you're asking stacked or layered questions. Second, practice isolating all the symptoms in your HPI into single questions.

It may help to visualize the concept of stacked questions as a slice of layered cake. It's too much for your patient to eat all at once. Best to give them one bite at a time.

Lastly, practice makes progress.

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