1. Department of Haematology; Aarhus University Hospital; Aarhus Denmark
2. National Research Centre for Working Environment; Copenhagen Denmark
3. Department of Haematology; University Hospital of Copenhagen at Herlev; Herlev Denmark
4. Department of Haematology; University Hospital of Copenhagen at Rigshospitalet; Copenhagen Denmark
5. Department of Haematology; Aalborg University Hospital; Aalborg Denmark
6. Department of Haematology; Odense University Hospital; Odense Denmark