In my role as a consultant in public health medicine with a focus on health intelligence and public health, I have often heard primary care clinicians quote what they term ‘anecdotal evidence’ in support of their viewpoint. This got me thinking about whether we should continue to use this term, in view of the importance of following evidence-based practice.
Four types of evidence have been described.1 Anecdotal evidence comprises a particular occurrence, whereas statistical evidence consists of an arithmetic summary of a series of instances. Causal evidence involves an explanation for the occurrence of an effect; finally, expert evidence comprises the opinion of one or more experts. Generally, anecdotal evidence is recognised as being based on personal experience, with anecdotes consisting of short stories or narratives that aim to make a point.
A 2005 review of the different evidence types found that anecdotal evidence is the least persuasive type of evidence.1 However, despite the findings of this review and also not appearing in the hierarchy of evidence,2 it has been argued that anecdotal evidence wields a disproportionally potent influence on clinical reasoning and behaviour.3
The words that we employ reflect our personal attitudes, and influence the mindsets of others. Pairing the word ‘anecdotal’ with the word ‘evidence’ implies that anecdote is a form of evidence when it is not, and also gives credence to any argument using it. For this reason, I would suggest that we detach the word ‘evidence’ from ‘anecdotal’ and replace it with the non-judgemental word ‘information’.
I am not arguing that we should not use anecdotal information, only that we should use it in its non-evidential context. Anecdotes can assist with clinical teaching, as well as help to influence professional or public opinion by relaying information in appealing, familiar, and personalised ways.3
- © British Journal of General Practice 2019
