TY - JOUR T1 - The future of diagnosis in general practice JF - British Journal of General Practice JO - Br J Gen Pract SP - 319 LP - 320 DO - 10.3399/bjgp20X710777 VL - 70 IS - 696 AU - William Hamilton Y1 - 2020/07/01 UR - http://bjgp.org/content/70/696/319.abstract N2 - ‘One finger in the throat, and one in the rectum, makes a good diagnostician’.1Things have moved on a bit since Sir William Osler’s times, though the importance of diagnosis in primary care remains. Indeed, despite the myriad investigations now available in healthcare, Osler’s emphasis on examination is still pertinent. Equally important, arguably more so, is good history taking. All these communication skills we’ve learnt and all the experience we gain from face-to-face contact makes us better diagnosticians. Yes, you know this, but I make no apology for repeating it. In essence, much of diagnosis in primary care happens without any tests at all. This includes diagnosis of the absence of disease, a key and underappreciated skill. However, three separate changes in primary care investigation are current: increasing use of existing investigations; new forms of testing; and new organisation of testing pathways, both in the UK and elsewhere.The only normal patient is one you have not tested enough; most medical students hear this quip at some time in their training. The volume of testing in primary care is mushrooming rapidly. For instance, around 10 million thyroid function tests are carried out each year in the UK with enormous variation in frequency across practices,2 while in comparison about 30% of the adult German population have thyroid function taken in any one year.3 This testing, arguably over-testing, is inextricably linked with diagnosis, and with over-diagnosis. For example, the median level of thyroid stimulating hormone (TSH) at which treatment is begun has fallen steadily to reach 7.9 mIU/l by 2009,4 despite a dearth of evidence … ER -