I was standing in the checkout queue in a local supermarket, when it was clear that I had been recognised. ‘Good morning David,’ he said brightly.

I looked to see who was speaking, but we were at that phase of the pandemic when everyone was wearing masks. I hadn’t a clue who was addressing me.

Then he made a comment about my needing a haircut, and I realised this personal comment was entirely appropriate.

He was the guy who normally cuts my hair. Recognising people in masks wasn’t a problem for him.

He recognised people by their hair.

It has always been a challenge recognising patients when away from the consulting room, and I know that I’m not the only GP to struggle with this.

It’s one thing feeling fully informed when you have the records. It’s quite another when you have no records or other clues to help.

However, what I found particularly disconcerting was realising that you didn’t know as much about your patients as you thought you did.

Elsie and Doreen were elderly ladies and both had been patients of mine for several decades.

Elsie was one of those patients who consulted me almost every week, often with the most inexplicable set of physical symptoms, and always with huge levels of overwhelming anxiety.

I had explored every aspect of her life, to try and understand the source of all her worrying and unhappiness. As a result, I thought I knew her well.

Meanwhile, Doreen was a lady of a similar age but one who seldom consulted me. She only came in when she needed a review of her ongoing medication. I knew her husband and children who all lived locally.

Then Elsie died. A few days later, Doreen came in to see me in a state of some distress, telling me how upset she was about her sister’s death. I still cringe, when I recall asking her who her sister was and trying to hide my surprise and confusion when it turned out that Doreen and Elsie were sisters. In 30 years of knowing them both, I had never worked this out.

You may well have experienced similar situations. The longer you are in practice, and the more you try to offer a degree of continuity of care for your patients the more you tend to believe that you know your patients well. Yet episodes like that of Elsie and Doreen kept on reminding me that I only ever knew part of their stories.

Perhaps the most challenging situations of all were those times when a patient told you something important about their life, which you never quite understood, but time was pressing and you didn’t try and clarify what they were talking about.

The next time the topic comes up, you feel too embarrassed to say you don’t really understand.

A few consultations later, it has simply become too late, and too embarrassing, to go back to square one. So your patient is sure you understand about this important aspect of their life, and you know for certain that you don’t.

Which is where a visiting medical student, or a consultation by a new GP registrar, can make all the difference. Someone who knows absolutely nothing about the patient has the enormous benefit that they can go back to square one, with a chance to get the full story. Then they can tell you what it is all about at a subsequent debriefing discussion.

But whether a student would have found out that Elsie and Doreen were sisters I very much doubt.