1. Division of Pediatrics, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
2. Department of Neonatal Medicine, Karolinska University Hospital, Stockholm, Sweden
3. Swedish Neonatal Quality Registry, Umeå, Sweden
4. Department of Ophthalmology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, Gothenburg University, Gothenburg, Sweden
5. Department of Pediatric Ophthalmology and Strabismus, St Erik Eye Hospital, Stockholm, Sweden
6. The Swedish National Patient Insurance, Stockholm, Sweden
7. Department of Clinical Sciences, Ophthalmology, Lund University, Lund, Sweden
8. Department of Clinical Science/Pediatrics, Umeå University, Umeå, Sweden
9. Department of Neuroscience/Ophthalmology, Uppsala University, Uppsala, Sweden