1. Department of Ophthalmology, University of Colorado School of Medicine, Aurora, CO, USA
2. Department of Biostatistics and Informatics, University of Colorado School of Public Health, Aurora, CO, USA
3. Colorado Department of Public Health and Environment, Registries and Vital Statistics Branch, Denver, CO, USA
4. Department of Pediatrics, Section of Neonatology, University of Colorado School of Medicine, Aurora, CO, USA