The problem-oriented medical record is a tool whose correct compilation meets the requirements of the law as well as the need for continuing medical education within the logic of clinical decision making. The reading of the contents of a record allows people to evaluate the correspondence between the "thinking" and the "doing" of a doctor, as well the objectivity of the facts--that is, the truth related to the reasons for a patient's admission to hospital and the nature of his or her illness. To this aim, the authors suggest a structural logical iter in concordance with the lines of hypothetical-deductive epistemology, in contrast to inductive epistemology, as tradition has always suggested. The latter, in fact, proposes to start from singular observations and proceeding, by successive steps, towards a diagnosis. It thus neglects to take error into consideration, and therefore the differential diagnostic process, and ignores the fact that one cannot pass from single descriptions to universal (diagnostic) laws on the basis of logic. The process of falsification therefore plays a central role in the diagnostic procedure and thus in the construction of the medical record. This falsification process is centered, according to the most recent epistemology, on the logical schemes of Popper-Hempel and Bayes. The authors propose an integrated combination of both schemes to enable a correct approach to diagnostic hypothesis and to differential diagnosis, with their relevant legal, didactic and administrative repercussions.