Whilst at a swimming pool with my kids, queueing for a waterslide, we saw a man lying prone on the ground, motionless.  Of course, I went over to see if I could be of any use.  

No-one was able to give me any history, apart form finding him on the floor.  No-one knew him, and no-one saw him fall.

I could get no history from him, so I examined him, and found him to be very drowsy, GCS 8 at best, and clearly "knocked off"/"altered".  There was no sign of a head injury but he was certainly not right.  I put him in a safe position, and spoke the the lifeguards to get an ambulance to take him to the local hospital.

*Then* a lady came up to talk to me.  She told me that the man was a history of learning difficulties, and frequently 'acts up' to get attention, often pretending to have had a heart attack or stroke.

At the IPCRG conference last week I described the stethoscope as a 'blunt instrument'.  Hyperbole to make a point that radiological imaging can be a useful tool, to help when the crackles in the chest don't give the answer.  Quite rightly a member of the audience pointed out that clinical examination is a vital part of our skillset, and perhaps the stethescope isn't as blunt as I suggested!

Of course the art of diagnosis isn't dependent on xhest x-rays, it starts, and often ends with the history.  I tell the students the same thing every year - diagnosis is 80% history, 10% examination, 5% tests, and 5% patience.  In the case of the fallen swimmer from my holiday, my examination suggested a serious intracranial event, and the definite need for hospital admission.  Once I acquired a history, everything changed.

So my lesson for the students - first take a history, and don't jump to conclusions without getting the best history you can.