Usability testing of a smartphone-based retinal camera among first-Time users in the primary care setting

Smartphone-based retinal photography is a promising method for increasing accessibility of retinal screening in the primary care and community settings. Recent work has focused on validating its use in detection of diabetic retinopathy. However, retinal imaging can be technically challenging and additional work is needed to improve ease of retinal imaging in the primary care setting. We, therefore, performed usability testing of a smartphone-based retinal camera, RetinaScope, among medical assistants in primary care who had never performed retinal imaging. A total of 24 medical assistants performed first-Time imaging in a total of five rounds of testing, and iterative improvements to the device were made between test rounds based on the results. The time to acquire a single ∼50° image of the posterior pole of a model eye decreased from 283±60 s to 34±17 s (p<0.01) for first-Time users. The time to acquire five overlapping images of the retina decreased from 325±60 s to 118±26 s (p=0.02) for first-Time users. Testing in the human eye demonstrated that a single wide-view retinal image could be captured in 65±7 s and five overlapping images in 229±114 s. Users reported high Systems Usability Scores of 86±13 throughout the rounds, reflecting a high level of comfort in first-Time operation of the device. Our study demonstrates that smartphone-based retinal photography has the potential to be quickly adopted among medical assistants in the primary care setting.