The importance of not despising keywords

A keyword is a word or short phrase that is used to describe the content of a study, using natural language terms. On the other hand, descriptors are standardized terms that documentalists use to index the study, using a controlled language that is much more specific than the natural one. Descriptors are grouped into dictionaries called thesauri, such as the MeSH of the National Library of Medicine or the Diccionario de Descriptores en Ciencias de la Salud of the Biblioteca Virtual en Salud. We describe the importance of the correct choice of descriptors and keywords, as well as the sources of where to obtain them.