Sammanfattning
In scientific studies, analysis of relevant and appropriate data material is a key factor. In this article we describe fundamental strategies for choosing appropriate data material and evaluating it. The aim of the article is to support nurses with an interest in research at degree level and beyond to choose appropriate data material for their studies, and to evaluate selection strategies in other studies. Our main finding is that there is no universal principle for selection, but that selection strategies should be adapted to the aim of the individual study and the research question, as well as the specific possibilities in the study situation. The article concerns selection of data in the most common medical science studies.