Most doctors treat simple medical problems similarly. The presenting problem leads to a single diagnosis, which leads to a treatment; all in an uncomplicated, linear pattern.

But in primary care, things are often not so simple. For multiple problems with complex underlying issues, no two consultations are ever the same. And a surprising amount of the variation depends on the doctor.

A shorter, edited version of this article will be published at The Conversation and a longer version will be published as a book chapter in late 2014. 

The non-linear consultation

When we think of what defines a medical consultation, we quite reasonably think of the ‘presenting complaint’: the medical problem which the patient brings to the doctor. In movies, literature, common wisdom and jokes, the doctor’s role is simple and rather passive—make the diagnosis and treat it.

Sure, some doctors might be more skilled than others—think of TV’s Dr House, who brilliantly diagnoses an incredibly…