References and bibliography

All references cited in the text must appear in the bibliography. The citation system most used in health sciences is that of compiling the bibliographic references at the end of the document as they appear in the text (ordinal method), indicating the corresponding number as a supra index or in parentheses (the footnote it must be avoided). Less used is the citation between parentheses of the author’s first surname and the year of publication. The way to identify the articles should be according to Vancouver standards. The review can be made from different methods of scientific information search: national or international journals, newsletters of organizations, books, searches through computerized systems (MedLine, MedLar) and personal communication with other researchers. The Internet offers a way of access to scientific information that is unrivaled in its richness, in the way of making a preliminary selection in a targeted manner and in its instantaneous availability (just a click-away). It should be borne in mind that the reviewers were often selected for their critical spirit and will rarely accept a statement contrary to their own perception without knowing the source of information.


This optional section includes secondary information or important material that is very extensive. The IP may have to be presented supplemented with a survey, maps or censuses, tables, addresses of the centers participating in the study, etc. In this case, they will be collected as annexes at the end of the project, taking into account that the attached information is really necessary and that it contributes something substantive in its assessment. It will be placed after the cited literature.

Formal considerations and useful advice. frequent errors

We must remember some recommendations that refer to the order in which the text can be constructed and written; to its adequate external form, which will contribute to an effective presentation and easy review of the organization, valuable aids for the understanding and analysis by the reader; and to the qualities of expression, which will facilitate and arouse the interest of reading.

A frequent error in the inexperienced researcher is to rush to write the PI when there is only a crude and unprocessed idea of ​​what you want to do. That way, some are able to do the initial manuscript in one go, but most do not. It must be remembered, therefore, that there is a logical order in the elaboration. The first step will consist in the elaboration of a scheme or script, provisionally composed of its different parts; it will consist, therefore, of names or phrases ordered hierarchically. Then the script has been expanded by phrases that refer to the fundamental ideas of each section to compose paragraphs, etc. Then the writing will begin, which will lead to the first draft that would complete the PI in its entirety -from the beginning to the end-, the complete manuscript, and which aims to achieve unity. From this previous draft and successive drafts will achieve its final drafting. In this last phase, a series of recommendations must be taken into account – review and correction – so that the work is worthily presented in its final version and ready for its issuance and distribution.