1. Department of Medical Biochemistry, Oslo University Hospital, Rikshospitalet, Oslo, Norway
2. Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
3. The Norwegian Dry Eye Clinic, Oslo, Norway
4. Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
5. Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
6. Department of Oral Surgery and Oral Medicine, Dentistry, University of Oslo, Oslo, Norway