With the exceptions of EMBASE, Agricola and the Internet, selection of articles from the library databases and the International Journal of Obesity were carried out in dupli- cate by two independent researchers blinded to each other’s selections. The continuously changing nature of the Inter- net impeded a duplicate selection. Because of time con- straints, selection was not carried out in duplicate for Agricola and Embase, which were added after the first search had been conducted. The investigative team settled discrepancies in selection decisions made in the duplicate search. Exclusion of many reports initially selected for inclusion occurred during the critical appraisal phase of the project, where close scrutiny of programmes was under- taken.
