The Company of Barbers (i.e. surgeons) was established in 1461 by Edward IV, in an attempt to deal with the problem of unqualified surgeons. By the time of Henry VIII, an examination was required to practise in London, overseen by the bishop of London and four qualified doctors. Also in London, four corpses (of criminals) were allowed each year for anatomy, i.e. dissection.
Dictionary of Medieval Terms and Phrases. Christopher Coredon with Ann Williams.