Diagnostic Error Under Scrutiny

9 September 2007 (Last Updated September 9th, 2007 18:30)

A delayed or missed diagnosis can be a nightmare for both patient and practitioner. Professor Mayur Lakhani, chair of the Royal College of General Practitioners, argues that more research is needed in this area and explores possible best practice for the future.

Every doctor will remember a clinical diagnosis that they have delayed or missed. This is one of the most powerful and distressing events in a doctor's life, particularly where a serious condition such as a brain tumour, meningitis or appendicitis is involved. The effect on patients is, of course, much more serious, and complaints and litigation often follow. In the UK, delayed diagnosis is the most common reason for successful medico-legal claims in general practice.

This issue has not received systematic attention, despite being one that can mean the difference between life and death. In fact, it is one of the least studied forms of medical error. The current approach is very much focused around litigation, punishment and blaming professionals, but we need a radical new approach to thinking about this problem in the context of developing patient safety systems and an open and fair culture.

THE EXTENT OF THE PROBLEM

Figures from the Medical Defence Union (MDU) show that more than half of the settled claims brought against GPs in 2003 were for a delayed diagnosis. Diagnostic error accounted for 51% of all GP claims and 60% of all costs.

"In the UK, delayed diagnosis is the most common reason for successful medico-legal claims in general practice."

It is likely that the overall burden is much greater, as many more cases will not reach the level of litigation. Other studies in 2003 revealed that error occurred between six and 80 times in 100,000 consultations. In a recent Healthcare Commission report, Spotlight on Complaints, 7% of respondents had complaints related to general practice.

Of that number, 66% cited problems with clinical care and treatment, specifically delays in referral or diagnosis. Patient concerns included alleged failures by GPs in making accurate or timely diagnoses, with a common complaint being that they should have been referred sooner for specialist treatment or further investigation of their symptoms.

GENERAL PRACTICE

Almost one million people visit their GP every day, and making an accurate diagnosis can sometimes be difficult because of undifferentiated presentations. Many problems in primary care do not lend themselves to a discrete diagnosis or label and it is one of the most important tasks – and strengths – of general practice to manage uncertainty and co-morbidity. The clinical method in general practice relies on formulation of a problem list, safety netting and arranging careful follow-up of patients, particularly those with vague presentations.

Marshall Marinker's distinction between the task of a generalist and a hospital specialist is useful for understanding the diagnostic function in general practice. Marinker says the role of the GP is to tolerate uncertainty, explore probability and marginalise danger. In contrast, the role of the secondary care specialist is to reduce uncertainty, explore possibility and marginalise error.

Although the distinction between a generalist and a hospital specialist must be understood and respected, an important factor in tackling missed and delayed diagnoses is breaking down the barriers between primary and secondary care. At present, the GP is often working without the ready availability of timely investigations, including imaging and access to specialist advice.

RARE DISEASES

Many patients with rare diseases, such as Kawasaki disease, myasthenia gravis and connective tissue disease, report not being diagnosed promptly or obtaining timely and meaningful support.

A GP's role becomes very difficult with rare conditions because the cardinal symptoms of these diseases have low predictive values. A rare disease is defined as a condition that affects five or fewer of every 10,000 people.

It is important to note that a rare disease may be more apparent to a GP who has knowledge of the overall set of symptoms than to a specialist investigating one subset.

WHY DO MISSED DIAGNOSES OCCUR?

The origins of misdiagnosis are complex. However, there are some recurring themes: failure to examine a patient; inadequate follow-up arrangements; insufficient investigations; and dysfunctional communication with patients and colleagues.

The issue is likely to become more important with NHS reforms bringing in more providers and multiple points of access. This, in effect, leads to personal and system discontinuity of care that may increase the risk of a delayed diagnosis.

A new and important emerging problem is practitioners having to deal with multiple presentations in a standard short consultation. It is not uncommon for a single patient to present four or five clinical issues.

MULTIFACETED SOLUTIONS

A multifaceted strategy is needed. Approaches to improving the diagnostic function include the use of algorithms; improving consultation and communication skills; better and faster access to imaging and specialist support; improved IT systems of clinical risk management; and measurement, learning and reporting to detect trends.

IMPROVING THE DIAGNOSTIC PROCESS

GPs are hampered in their efforts to provide best clinical care by a lack of access to diagnostics – many of which are only available through consultant referral – and this creates bottlenecks and waiting lists. There needs to be a concerted effort by the NHS and commissioners to bring more diagnostics and better services to the community.

"GPs are hampered in their efforts to provide best clinical care by a lack of access to diagnostics."

The Royal College of GPs (RCGP) and the Royal College of Radiologists (RCR) have developed a "Framework for Primary Care Access to Imaging – Right Test, Right Time, Right Place", which supports GPs by indicating appropriate diagnostic imaging strategies for patients with a range of common clinical problems.

It provides guidance on the most appropriate investigations for over 60 common adult clinical conditions for which direct access to imaging should be available from primary care. It supports access to imaging by GPs equivalent to hospital doctors on the basis of the health and clinical needs of patients.

Similarly, cancer referral guidelines issued by the National Institute of Clinical Evidence (NICE), implemented using decision support, may be helpful in managing referrals and prioritising patients. It is neither possible nor sensible to teach GPs about every disease that is known; rather it is better to enhance generic professional and clinical skills.

DEALING WITH TEST RESULTS

GPs must ensure that their practice systems are effective at dealing with test results. Consider the guidance from the Royal New Zealand College of General Practitioners: GPs must ask themselves whether their systems can detect overdue and missing results; highlight whether serious pathology or significant results are expected; and notify patients if results are copied to their practice from hospitals and out-of-hours service providers.

The onus should be on the general practice to notify patients of their test results – not on the patients to find out. Crucially, GPs must make sure their patients understand their notification policy.

Diagnostic errors can be minimised by improving GPs' systems and ensuring that there are good communications between all providers of care. Also needed is an effective system of dealing with results from different requesters and making information available at the right time.

A perfect system that ensures every patient is followed up and that all test results are dealt with is extremely difficult, if not impossible, to achieve, but practices can reflect on their own systems for managing tests and referrals and consider whether any improvements might be made. Key to achieving this is ascertaining the robustness of risk-management systems.

LEARNING AND REFLECTION

When a diagnosis is missed, the patient and the family need support. Professionals need training, skills and facilitation to help do this in an open and fair manner. Doctors involved in this also need to be supported and to learn by using the technique of significant event auditing.

The RCGP has issued the first ever GP curriculum and for the first time, the subject of patient safety will be an integral component of the GP training programme. Drawing largely on the National Patient Safety Agency's good practice guide, Seven Steps to Patient Safety for Primary Care, the curriculum statement advocates embedding patient safety at individual doctor-patient, GP practice and community levels.

Presented in the form of specific learning outcomes that all GP registrars should achieve, it recommends working with patients to assess and discuss risk and then design solutions to prevent incidents occurring.

The use of a reporting and learning system is essential to better understand missed diagnosis and to start to formulate solutions. As part of professional development, GPs must reflect on such issues. One RCGP assessment (Fellowship by Assessment) standard states that:

The candidate must demonstrate a commitment to the principle of early diagnosis by retrospectively surveying the care of samples of patients seen by him/her and:

  • Checking for ten malignant and ten non-malignant conditions
  • Examining the interval between first presentation and appropriate action
  • Learning and reflecting

Prompt and secure diagnosis is an important function of medicine. Measures of diagnostic error need to be developed in the NHS as a whole, and the health community needs to accelerate research into novel preventative strategies.

"The use of a reporting and learning system is essential to better understand missed diagnosis and to start to formulate solutions."

There must be an honest acknowledgement that errors will occur in primary healthcare. While greater vigilance is needed, it is important not to over-investigate routinely or over-refer (the "just in case" referral or investigation).

However, if a patient is under hospital care, it is vital that the GP is kept aware of their progress. Coordinating and integrating care is an important part of the GP role, particularly as many patients have co-morbidity. The key groups are the patients who do not improve, or show an unexpected clinical course. In the case of children, the GP must listen avidly to the concerns of parents.

Later this year, the RCGP will publish its roadmap to the future of general practice. This landmark document recognises changes in society over the last 30 years and the increasing role of the patient in determining healthcare and its provision.

A new dialogue is emerging between healthcare consumers and providers, and in future, patients will be equipped with the knowledge and skills to navigate a complex healthcare system, working with a trusted health professional, often a GP.

The future of general practice will lie in enabling patients to take ownership of their health needs. This shift in attitude will go a long way in helping reduce the risk of misdiagnosis.