Self diagnosisBMJ 2009; 339 doi: https://doi.org/10.1136/bmj.b4418 (Published 11 November 2009) Cite this as: BMJ 2009;339:b4418
- Clare Goyder, academic foundation year 2 in general practice 1,
- Ann McPherson, university lecturer, medical director2,
- Paul Glasziou, professor of evidence based medicine1
- 1Department of Primary Health Care, University of Oxford, Oxford OX3 7LF
- 2Health Experiences Research Group (formerly DIPEx), Department of Primary Care, University of Oxford, Oxford OX3 7LF
- Correspondence to: Clare Goyder
A 26 year old postgraduate student presents with a 12 hour history of a painful left eye. She feels her vision is reduced and her eye is watering more than usual. She has had a previous episode of iritis (anterior uveitis) and she suspects that this is the diagnosis today.
What is self diagnosis?
The process of diagnosis is pivotal to the daily work of the general practitioner. Despite the clinical importance of this process, many of the diagnostic methods used by GPs have been elucidated only recently. Three key stages in diagnostic reasoning have been identified (fig 1⇓).1 In the first stage diagnostic hypotheses are triggered, and sometimes this is done by the patient: “Doctor, I think I have the flu/gout/tonsillitis/etc.”
When is it used?
Several processes can initiate diagnostic hypotheses (fig 1⇑). The most common is the patient presenting with a particular key symptom. The “presenting complaint” is used in the initiation phase in almost 70% of consultations with general practitioners.1 Patients also present with preconceived diagnoses that may explain their symptoms. Heneghan et al found that this process of self diagnosis (also called self labelling) was responsible for initiating a diagnosis in 18% of consultations.1 Conditions that were commonly self diagnosed included tonsillitis, gout, and chest infections. Using this process well relies on giving patients time to tell their story and then asking open questions, such as “What are you worried about?” or “Did you have ideas about what this might be?” General practitioners can then explore where these preconceived ideas originated.
The few studies that have been performed on the accuracy of self diagnosis suggest that …