Methods: A decision tree model was built with life years gained as outcome, from the perspective of the health system, and including all direct costs. Pharmaceutical prices were obtained from the System of Information of Medicaments SISMED (2008), and the value of procedures was calculated from the 2001 ISS tariff manual adding 30%. All monetary amounts were expressed in Colombian pesos of 2010. No discount was applied as costs are incurred in during the first year. The cost-effectiveness threshold used was three times the 2010 per capita GDP per life year gained. Univariate and probabilistic sensitivity analysis were performed over the variables having the higher effect on the incremental cost-effectiveness ratio (ICER).