Guzzo, A.S., Meggiolaro, A., Marinelli, E., La Russa, R., D’Ambrosio, M.G., AND La Torre, G.. " The case of Patient Safety Indicator 12 (PSI12): use of administrative data to estimate the incidence of “Postoperative Pulmonary Embolism or Deep Vein Thrombosis”. A pilot study in a General Hospital" La Clinica Terapeutica [Online], Volume 1 Number 170 (14 February 2019)