From this patient’s perspective, the ‘Easily missed’ and ‘Diagnosis’ series begun in the BMJ last year are particularly welcome. Many physicians are described informally as ‘diagnosticians’ but, as a layman, I wonder whether there may be a case for formalising such a specialty or sub-specialty.

Editing the BMJ’s series of Patient Journey articles provides an interesting overview of the aspects of their care that trouble patients most. The consistent thread running through their stories, and the one most widely cited within patient support groups for people with chronic conditions, is the length of time it can take to obtain an accurate diagnosis.

Doctors are probably more comfortable with uncertainty than patients, who may want a formal diagnosis for a variety of reasons, ranging in importance from their need for a ‘shorthand’ with which to explain their affliction to friends and family, to the belief that it is better to treat an illness than its symptoms and that an illness cannot be treated unless it has been clearly identified. Most serious of all, of course, are the missed diagnosis or misdiagnoses of potentially fatal conditions or disabling ones. Gill Reeve’s account of her ovarian cancer (BMJ 2009;338:b2072) was an example of the former. An example of the latter will be seen in Teresa Harding’s account of her 20-year wait for a diagnosis of the cause of her severe disability, due to be published shortly.

Ironically, it may be that the increasing sophistication of medicine is undermining clinicians’ ability to provide rapid, accurate diagnoses. GPs, expected to know about an ever-widening range of illnesses and treatments, will inevitably know less about any of them, unless the condition is one in which they have a specialist interest. I do not envy their responsibility for separating serious conditions from transient and relatively inconsequential ones presenting with very similar symptoms.

Two of the effects of medicine’s increasing sophistication are more easily seen in secondary than in primary care, firstly with increasing specialisation, sub-specialisation and sub-sub-specialisation, and secondly, as a corollary, with the apparent loss of the ‘general physician’. With possible symptoms of cancer of the colon, you will be sent to see a gastro-surgeon. When the diarrhoea and unexplained but rapid and dramatic weight-loss are shown not to be caused by cancer, you will be referred to a gastroenterologist. Throw in pre-existing thyroid disease and other concurrent symptoms such as anaemia or osteoporosis, and you will begin shuffling back and forth between haematologists, endocrinologists and rheumatologists, with a wait to see each specialist and to undergo each test. There seems to be no one to take an overview of the case, to establish whether the symptoms – or at least some or most of them – are caused by a single underlying condition.

A complicating factor about which patients also complain is lack of continuity of care. In General Practice, and especially for urgent appointments, one rarely sees the same doctor twice. In secondary care, one almost never does. We may be seen by a specialist for the first appointment but are confronted thereafter with an ever-changing kaleidoscope of specialist registrars, few of whom have had time to read our notes in detail and fewer of whom are in a position to take an objective overview of a complex case or to pull together the threads that might be woven into an accurate diagnosis.

It is widely accepted that patients prefer their healthcare needs to be met as close to home as is commensurate with high quality services – that is to say, in primary care. I wonder whether a solution to the problems associated with complex or difficult diagnoses, or at least a partial one, might be found in the establishment by Primary Care Trusts of posts for ‘GPs with a special interest in diagnosis’.

The doctors concerned would need to be experienced, inquisitive and tenacious, and to be trained in the diagnosis of complex conditions. They would be relieved of a sufficient proportion of their routine caseload to allow them to spend more time with each patient. Other GPs within the PCT would be able to refer to them patients with persistent illnesses which failed to respond to conventional treatment, and patients with persistent multiple symptoms which appeared to point to a particular underlying condition but the tests for which had proved negative. Their role might be to take a fresh, objective overview of each case, to pull together the threads of the various symptoms, to be prepared to think laterally, and to develop sound relationships with local specialists in secondary care. They might also have a responsibility to familiarise themselves with a range of rare diseases and their symptoms. Importantly, too, they would be expected to provide continuity of care, seeing each patient as often as necessary until a conclusion is reached.

Such a scheme could not be expected to guarantee accurate and timely diagnosis in every case, but it might go some way towards doing so and, importantly, it would help reassure patients that everything possible was being done to help them.

Peter Lapsley is patient editor of the BMJ.