Statistics for the European Respiratory Journal.

This review summarizes statistical methods likely to be needed by researchers. It is not a replacement for a statistics book, and almost no symbols or mathematics are used. It seeks to guide researchers to the appropriate methods and to make them aware of some common pitfalls. Sections deal with methods for quantitative outcomes, both basic and more advanced, and parallel methods for qualitative or categorical outcomes. Reference is made to papers using the more advanced methods in the European Respiratory Journal in order that their relevance may be appreciated. The paper seeks to improve the quality of papers submitted to the European Respiratory Journal, to reduce the revisions to papers required of authors, and to enable readers of the journal to gain more insight into the interpretation of results.