To err is human – Diagnostic errors and medical negligence

A recent study published in the Medical Journal of Australia shows that of all the medical errors that occur in Australia each year, approximately 140,000 relate to misdiagnosis or delays in diagnosis. About 21,000 of those medical errors cause serious harm and result in about 2,000–4,000 deaths. Errors in diagnosis represent almost half of medical negligence cases against general practitioners.

So, what is going on and what can be done about it?

In 75% of cases involving misdiagnosis, the culprit is the cognitive bias of the medical practitioner, including:

• overconfidence in an incorrect diagnosis; and
• failure to find a differential diagnosis.

Incredibly, systems errors such as missed communication or follow-up of results were much less frequent. And only 5% of all diagnostic errors were found to be because of a lack of knowledge by the doctor.

In simple terms, the majority of these medical errors occur because of “blinkered thinking”.

So how can doctors and their patients help to take these blinkers off?

For doctors:

Back to basics: The MJA authors note that taking a good patient history and undertaking an adequate physical examination will result in correct diagnosis in ‘more than 80% of cases’. Conversely, a failure to do so contributes to ‘40% of missed diagnoses’.

If a patient presents with undifferentiated symptoms, remember that it is OK to structure a follow-up time with the patient. Telehealth represents a great opportunity to make a time to follow up with the patient.

Avoiding cognitive biases and errors is less simple.

The study recommends:

1. Feel comfortable being uncertain: be prepared to share and explain uncertainty about diagnosis with your patients. Remember that about 40% of all initial presentations do not yield a definite diagnosis.
2. The study identifies a number of strategies for reducing cognitive biases and errors. These include:

• Adopt cognitive forcing strategies that require you to slow your thinking and to methodically evaluate potential alternatives.
• Share with colleagues: engaging other clinicians in solving diagnostic mysteries
• Continuing education: engaging in seminars and lectures, group discussions, and online learning;
• Keep diagnostic checklists to assist with differential diagnoses.
• Following up with patients and colleagues – ask them to report errors and implement protocols for identifying those errors.

Remember that your decision-making will be worse if you are under time pressures, experiencing stress, fatigue or other distractions and these can all add to the chance of cognitive error.

For patients:

Here are the 6 things that you can do as a patient to give yourself the best chance of getting the correct diagnosis and treatment from your local doctor.

1. Ensure that the doctor performs an examination and takes down an accurate history;
2. If you’re seeing a new doctor at your usual clinic, be sure to point out to them any aspect of your medical history which you think might be relevant;
3. Feel confident in asking questions, such as:
   1. What should I do if this does not improve in the next (hours/weeks/days)?
   2. What else could this be?
   3. Is there anything else I can do to investigate the problem further?
   4. What should I do if I can’t see the specialist/have the tests done straight away?
4. Don’t leave the consultation without a clear plan. Understand what will happen next and ask for a time frame so that you know when you’ll take that next step;
5. Don’t allow a rushed appointment. When you are in a consultation with your doctor, you should be their primary focus. Do not allow yourself to be rushed through your consult just because the waiting room is busy, or because the doctor looks stressed or tired;
6. Follow up on your results. If you’re waiting on results or a referral, be sure to follow up with your doctor to ensure that it hasn’t fallen through the cracks; and
7. Seek a second opinion. So many of our clients say that they felt like they hadn’t been heard, or that they wished that they had trusted their gut and sought a second opinion. Challenging a trusted doctor can be difficult for patients, and so can demanding the time and attention you need to have your health concerns investigated. If you don’t feel like you’ve been heard by your doctor, you should seek a second opinion.

It is important to understand that not all diagnostic errors will lead to disciplinary complaints or medical negligence claims.

As professionals in this field, we talk about the “swiss cheese” effect. That is, a claim will only occur where all of the errors or circumstances align. These include:

1. That a missed or delayed diagnosis has occurred;
2. That the error is not detected or corrected promptly;
3. That the error has caused permanent or significant injury, or death;
4. If the correct diagnosis had been made earlier, there would have been a significantly improved long term outcome;
5. That a claim relating to the injury or death would result in compensation being paid which outweighs the costs of litigation; and
6. Where the injured person engages a specialist lawyer.

Whether or not we will continue to see significant errors in diagnosis will depend on a number of hard and soft factors.

1. It is arguable that the empowerment of patients and an increase in access to information might lead to a decrease in the number of patients suffering the effects of a missed or delayed diagnosis by their doctors. This is particularly so when they are prepared to ask questions or get a second opinion.
2. Secondly, improved use of technology such as portable e-health records and the long overdue death of the fax machine could see an improvement in the moderate contribution of technology or systems in missed diagnosis.
3. Lastly, the preparedness of doctors to acknowledge, share, review and correct mistakes will be critical in reducing the number of diagnostic errors. Peer support, ongoing education, debriefing, healthy workplace cultures all contribute to the way that we perform our roles as professionals.

In a health system which, by and large, delivers extraordinary results for patients across Victoria, it is reflection, rather than perfection, that patients should be entitled to expect from our local medical practitioners.