Advanced Technique - Differential Diagnoses

These are very common questions, and probably the least complex of the lot. They tend to come in a set format, but as ever, the exact wording of the question changes the entire interpretation.

This one is a little tricky to explain on the PassGP Academy so our examiners will show you this in detail in the question banks.

For now, remember to:

• Be specific – the more specific the answer the higher the marks.
• Don’t overcode
• Don’t fall foul of capping by giving differential diagnoses that are too similar.

Here is a worked example:

James Bashford, aged 52 years old, presents with a six-week history of new onset lower back pain and left lower leg weakness. On examination you note the presence of numbness over his left big toe and and inability to flex it.

What are the most likely initial diagnoses? Write two (2) answers.

(Maximum score = 3 marks)

Answers permitted:

• Lumbar disc prolapse (2 marks; Group 1)
• Radiculopathy (1 mark; Group 1)
• Pathological fracture (1 mark)
• Malignancy (1 mark)
• [All other answers would not score]

If you were to write down.

• Lumbar disc prolapse 
• Radiculopathy

You would only score 2 marks (not 3) as they are capped.

If you were to write down “nerve pain” you would score nothing, as it is not specific enough.

Be specific, don’t overcode, avoid being capped.

That will do for now – onto the next lesson!