In this master thesis, we have analyzed the role of the Adherence to the Mediterranean Diet (mdscore) on global mortality and have performed a comparison of Cox's proportional hazards model and the Flexible Parametric PH model proposed by Royston and Parmar (2002). This study include individuals from five Spanish regions of the European Prospective cohort into Cancer and Nutrition (EPIC-Spain). Both fitted models consider the mdscore as the main variable, are stratified by sex, center and age at recruitment, and adjusted by potential confounders such as: smoke status, BMI, physical activity, energy intake, waist circumference and educational level.