An edge-punch card system as an aid to differential diagnosis of common childhood diseases has been developed. This should be a valuable tool in teaching differential diagnosis to medical students and as an aid to practicing physicians.
Athreya BH, Athreya RB, Coriell LL. Edge-Punch Card as a Tool in Differential Diagnosis. Am J Dis Child. 1970;119(1):53-56. doi:10.1001/archpedi.1970.02100050055011