• A simple mechanical binary search device is described that can be used to perform the Parks' three-step test. Instructions to make the device from light cardboard are provided.
Perlman EM. A Mechanical Three-Step Test. Arch Ophthalmol. 1984;102(11):1712. doi:10.1001/archopht.1984.01040031396035
Customize your JAMA Network experience by selecting one or more topics from the list below.
Create a personal account or sign in to: