This case is an example of a type of bias in the way we think, which complicates decision making in many professions, particularly medicine. This is a type of cognitive bias, in this case termed a confirmation bias, where the practitioner favours and searches for information to confirm what they already think they know, or an ideal outcome they would like to achieve.

A lady presented with severe chest pain radiating through to her back and right shoulder. The GP initially felt this may be either cardiac in nature, due to a lung infection or a pulmonary embolism, and had already commenced her antibiotics.

In the Medical Assessment Unit, a chest x-ray was clear, and she had no raised temperature. She did, however, have a high white cell count of 20, a high CRP (marker of inflammation) at 150 and a raised bilirubin, although on day one there was no change in her liver enzymes, which consequently became raised.

The medical team concentrated on ruling out pulmonary embolism with a specialised CT scan, which was clear. She had some tenderness over her lower ribs and, therefore, it was decided that she had some inflammation in the area (costo chondritis), so she was discharged on anti-inflammatory medication with a diagnosis of either inflammation or a viral chest infection.

Her condition settled over the next few days while she continued her antibiotics. Two weeks after stopping them, she became ill again with severe lower chest pain radiating to her back and her right shoulder. She was admitted to another hospital, where an ultrasound scan of her abdomen revealed a swollen gallbladder with gallstones. She underwent a laparoscopic cholecystectomy, which confirmed the significant inflammation around the gallbladder, from which she made an uneventful recovery.

She consulted her solicitor in relation to taking action against the first hospital for not diagnosing her cholecystitis with gallstones, and proceedings were initiated on the basis of a GP note and records from the two hospitals.

An expert report was commissioned, which pointed out that there was indeed substandard medical care in not organising an ultrasound of the gallbladder in someone with severe lower chest pain radiating through to the chest and shoulder, coupled with abnormal liver function tests, a high white cell count and a raised CRP. However, it also pointed out that the cholecystitis had responded initially to the antibiotics, which she had been put on for other reasons. She started to develop pain again after they were stopped, a correct diagnosis was made, and the gallbladder was removed.

Cognitive bias, in this case a confirmation bias, is an example of one of the most common causes of misdiagnosis in which a doctor comes to a conclusion and then attempts to prove it, as opposed to keeping an open mind when the facts and the investigations do not fit.

In many institutions, acute cholecystitis is treated with antibiotics and then an interval cholecystectomy planned for six to eight weeks, and this would be regarded as a reasonable standard. In the event, she did have her gallbladder removed within six weeks, and so, although there was substandard medical care in the first hospital, there was no “consequential damage” in terms of the procedure ultimately required and the timescales involved; therefore, an action in negligence would be unlikely to succeed.

This again is another example where proper screening in that the plaintiff’s initial complaint was obvious the time and effort by the solicitor and provided a proper explanation to the plaintiff.

MDU figures for 2020 show that less than one in six actions in medical negligence actually succeed, with the vast majority failing on the grounds of causation. It must be remembered that subsequence is not the same as consequence.

Initial screening is therefore essential to manage client expectations at an early stage. This avoids unnecessary effort and costs for all concerned. Too many cases are taken to Court with no chance of success. This is stressful for both the client and their legal advisor, and indeed for the medical personnel involved.

For fast and effective screening of all potential medical negligence cases, contact Peyton Medico Legal Services now on +44 (0)28 87724177 or email [email protected]