1. Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
2. Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
3. The Norwegian Dry Eye Clinic, Oslo, Norway
4. Department of Ophthalmology, Vestre Viken Hospital Trust, Drammen, Norway
5. Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway