1. Medical Council; Research Department; Lynn House Lower Rathmines Road Dublin Ireland 6
2. Cochrane Occupational Health Field; Finnish Institute of Occupational Health, Center of Expertise for Good Practices and Competence, Team of Knowledge Transfer in Occupational Health and Safety; PO Box 93 (Neulaniementie 4) Kuopio Finland 70701
3. University College Cork; Department of Epidemiology and Public Health; Cork Ireland