The selection of the doctors of tomorrow is a subject of constant interest because it raises questions about ensuring equity, predicting human behaviour, and defining the characteristics of a good doctor. In the United Kingdom, it costs about £200 000 (€260 000; $400 000) to train each medical student, but the cost of getting the selection wrong is much greater.

Selection takes place under considerable time pressure—in the UK around 19 000 applicants must be screened for some 8000 places in less than six months, and each applicant may apply to four medical schools. The selection ratio in the United States is remarkably similar—around 42% of 42 000 applicants were successful in 2007, although each student made an average of 13 applications.

Different specialties have different requirements, but from our reading of the literature we distil three broad attributes that doctors should have—cognitive ability (including linguistic and mathematical intelligence, problem solving capacity and memory); humanity (kindness, empathy, emotional intelligence, bedside manner and …