This work aims to determine and quantity the scientific production that researchers can deposit at institutional repositories. It applies a methodology based on the analysis of the access models of journals used by researchers to publish their articles to estimate the actual and potential access to scientific research outputs. It includes the case of the field of Medicine scientific production from 2006-2010 of two Argentine national universities. Methods: The scientific production at National University of La Plata (UNLP) and National University of Rosario (UNR) was determined by taking a sample from Scopus and the journal access models established through searches performed using Romeo-Sherpa, Dulcinea, DOAJ, SciELO, RedALyC and PubMed Ce...