La Comorbidità e lAgire Medico: Il caso degli ipotrattamenti nella cura del tumore della mammella

When a physician has to come to a decision while caring for a given patient, he is supposed to take into account several kind of information related to the disease, illness or patients' personal characteristics. Although it is well known that the framework in which such decision has to be taken is complex, most of the scientific knowledge is based on pieces of evidence that derive from studies where complexity is avoided by applying restriction rules. The goal of this approach is to enhance the internal validity while preserving the generalisability of the findings. But in some cases this approach raises more doubts than certainty. It is the case of the process to assemble practice guidelines to reduce the gap between the best care and what is observed into practice using the available knowledge (i.e., available literature or experts' recommendations). As a variety of relevant clinical and patients' personal characteristics are not available at all or little is known on their impact on patients global health status, variables that actually do drive the practice are not included in guidelines that are intended to change it. This paper introduces the conceptual model of such debate and assesses the impact of co-morbidity--a variable seldom taken into account in effectiveness, quality and appropriateness studies- on the kind of medical care given to a sample of 1019 patients with early stage breast cancer. Empirical results and future implications are eventually discussed.