[Motives for non-vaccination: critical review of the international literature, 1950-1990].

Many countries have acknowledged that vaccination programs call for a mastery of technical and organizational elements if they are to become accessible to the population. One of these elements has been greatly underestimated: the participation of populations and their motivations. Experiences in several countries are here analysed, on the basis of a bibliographic revision of the period 1950-1990. Results show that existing studies vary in their conceptual and methodological focuses, according to the region in which research was carried out and to the kind of researcher involved. This fact is to be explained by the posture, common among researchers, of believing that they know in depth the subjective determinants of the behavior of the societies to which they belong. Based on this, they only use methodologies that allow them to arrive at a superficial understanding regarding the response of populations to the offer of vaccines.