1. University of Bern; Institute of Primary Health Care (BIHAM); Gesellschaftsstrasse 49 Bern Switzerland 3012
2. Fondazione "Università G. D'Annunzio"; Centre for Systematic Reviews; Via dei Vestini 31 Chieti Chieti Italy 66100
3. University of Bern; Institute of Social and Preventive Medicine (ISPM); Finkenhubelweg 11 Bern Bern Switzerland 3012
4. Inselspital Bern; Department of General Internal Medicine; Freiburgstrasse 4 Bern Switzerland CH-3010
5. University Hospital; Department for Rheumatology, Clinical Immunology, and Allergology; Inselspital Bern Switzerland