1. Danube University Krems; Department for Evidence-based Medicine and Clinical Epidemiology; Dr.-Karl-Dorrek-Str. 30 Krems Austria 3500
2. Danube University Krems; Cochrane Austria; Dr.-Karl-Dorrek-Str. 30 Krems Austria 3500
3. Royal Far West; PO Box 52 Manly NSW Australia 1655
4. Ludwig-Maximilians-University Munich; Institute for Medical Informatics, Biometry and Epidemiology; Marchioninistr 13 Munich Bavaria Germany
5. Leibniz Institute for Prevention Research and Epidemiology; Research Group for Evidence-Based Public Health; Achterstr. 30 Bremen Germany 28359
6. University of Bremen; Institute for Public Health and Nursing Research, Health Sciences Bremen; Bibliotheksstr. 1 Bremen Germany 28359
7. University of Pécs; Cochrane Hungary; Rákóczi Str. 2. Pécs Hungary H-7623