1. Cochrane Occupational Safety and Health Review Group; Kuopio Finland
2. Finnish Institute of Occupational Health; Cochrane Occupational Safety and Health Review Group; PO Box 310 Kuopio Finland 70101
3. Finnish Institute of Occupational Health; Lemminkäisenkatu 14-18 B Turku Finland 20520
4. University of Maryland Baltimore; 110 South Paca Street Rm 4-S-100 Baltimore Maryland USA 21201
5. University of Toronto; Dalla Lana School of Public Health; 155 College Street, 6th floor Toronto Ontario Canada M5T 3M7