Los términos: eficiencia, eficacia y efectividad ？son sinónimos en el área de la salud?

the terms efficacy, effectiveness and efficiency are frequently used under circumstances that make them have different meanings. they may take numerous meanings depending on the field where they are applied (medicine, management, engineering, etc.). some of their definitions are analyzed in this paper, starting from the ones appearing in the general dictionary to those used in the health sphere, aimed at understanding the different meanings and at using the most appropriate in each situation. finally, efficiency is defined from the economic point of view as the attainment of objectives by the election of alternatives thay may produce the greatest benefit expressed by the quotient of the obtained results and the value of the resources used. on the other hand, efficacy is defined as the objectives/results ratio under ideal conditions, whereas effectiveness is considered as the objectives/results ratio under real conditions.