5 types of medical bias
We all have biases. We all have weaknesses. We should not – but we do. But you can learn to recognise and reduce them.
When you first start off as a doctor, the primary motive for taking a history is information gathering.
But as you transition to fully-fledged doctor history-taking, a rigid process becomes a more dynamic one – involving a complex interplay between you and the patient.
You will be obtaining and synthesising information to increase or decrease the pre-test probabilities (a set of differential diagnoses).
So you need to aware of the biases that can get in the way of history-taking.
So. What are 5 examples of bias in medicine?
1. Overconfidence (arrogance) bias
“I’m an amazing diagnostician, I must be right!” or “I rarely make mistakes” or “I’m very popular with my patients and colleagues” – common in doctors.
2. Confirmation bias
Paying attention to those aspects of the history that fit what you think is going on, at the exclusion of seeking more information to explore other differentials – i.e. fitting the diagnosis into your pre-decided one (and treatment plan).
I.e. don’t decide on your diagnosis too early!
3. Availability bias (common diagnoses going around)
“I’ve diagnosed a lot of gastroenteritis today, so this abdominal pain must be gastroenteritis”.
4. Personality bias
Allowing positive or negative feelings towards a patient influence the completeness of your history-taking.
You are not their friend (though should be friendly) and you should try not to like/dislike them.
This can make you over depend on their views – e.g. “I like this very sensible chap, so I will give him my email address; and I’m sure he will chase his own blood tests and let me know if they are abnormal”.
You need to be objective with all patients (whether you like them or not).
Try to develop your own (reliable) system of assessment, investigation and chasing those investigations.
If you send a test off (even in someone else’s name) its your job to chase and respond to it. It is not ‘the system’.
5. Judgement (of class) bias – do not judge the patient
‘The nun (or doctor!) is as likely to have syphilis as the prostitute’ (maybe not entirely true, but you know what we mean).
I.e. do not make a judgement on a patient based on their class, race, gender, sexuality, job or appearance.
Fridays
Rare things – or diagnoses that need to be challenged – present on Fridays. So you need to have least bias on a Friday. They are tired. You are tired. So, have a strong coffee, clear your brain, and start again.
Summary
We have described the 5 types of bias in medicine. The literature suggests the first step to overcoming these biases is to be consciously aware of them. What are yours?
