Abstract
The abstract is the precise summary of the article, not a preface. As Baue wrote in a popular editorial of the Archives of Surgery in 1979, "writing a good abstract is not abstract writing" [6]. The main data have to be represented, as they allow readers to understand contents clearly. Sentences like "The paper reports..." or "The authors describe..." have to be avoided as well as any generic statements.In order to help writers avoid generalities, the recently revised version of this journal's "instructions to authors" [4] requires the abstract to be no longer than 300 words and structured in 4 paragraphs: the Background declares the hypothesis, the Materials and methods impart the study design and quote the relevant numerical features of the samples, the Results report the main data and their statistical significance, the Conclusions state whether the hypothesis is verified or not. One or two sentences per paragraph are usually sufficient.The abstract is frequently recommended to be written after the text, as "the process of writing changes thought and perhaps even purpose" [7]. Nonetheless, in my view, preparing the abstract first is a useful exercise that forces the authors to organize their thoughts and guides the organization of the article. However, the abstract should be always revised after the manuscript has been completed.