1. From the Vision Assessment Unit, Department of Ophthalmology, Royal Liverpool Children’s Hospital, Liverpool, United Kingdom; the2Unit of Ophthalmology, University of Liverpool, Liverpool, United Kingdom; and the3Infant Vision Laboratory, The Smith-Kettle
2. From the Vision Assessment Unit, Department of Ophthalmology, Royal Liverpool Children’s Hospital, Liverpool, United Kingdom; the
3. Infant Vision Laboratory, The Smith-Kettlewell Eye Research Institute, San Francisco, California.