The format was originated by the Florentine doctor of medicine Taddeo Alderotti, under the pressures for down-to-earth advice, based on experiential observations, in treating the Black Death that decimated Italy in 1348 and recurred at generational intervals for the following centuries.
Medieval medical writings had tended towards theory rather than praxis, which was denigrated as ars mechanica, mere technician's work unsuited to the higher intellect.