The reliability of results from observational studies has been called into question many times in the recent past, with several analyses showing that well over half of the reported findings are subsequently refuted. In an effort to improve the quality of epidemiological studies and their design, an international group is developing publication guidelines for observational trials, similar to the CONSORT guidelines that were adopted for randomized trials. The proposed guidelines, called STROBE (STrengthening the Reporting of OBservational studies in Epidemiology), will provide a checklist that authors and journal editors can use to ensure that the necessary information has been included in a manuscript. The checklist will in clude both basic study design information, such as stating the specific objective and prespecified hypotheses, and more complex elements regarding the handling of quantitative variables and statistical methods.