Can Applications Designed to Evaluate Visual Function Be Used in Different iPads?

Abstract

Statement of Significance: Apple devices could be suitable for vision tests, provided that the test has been correctly adapted to the device, taking into account the spatial and colorimetric characterization of the screen. Purpose: The majority of vision apps have not been developed by vision or colorimetry experts and suffer from conceptual and design errors that may lead average users to an erroneous assessment of their visual capabilities. The reliability of vision tests depends on the accurate generation of the necessary visual stimuli in a particular device. Our aim was to ascertain whether a given colour test, designed for a colorimetrically characterized device, might be used in another similar device. Method: We evaluated colour reproduction errors in three iPad tablets of different models with Retina screens, using their individual colour characterization models and the model derived for another device. Results: Our results showed, even with this small sample, the high degree of error caused when disregarding the fact that the colorimetric design valid for a given device may not be correct when displayed in another. Conclusion: The distortion of the chromatic content may lead to subjects with vision defects to pass as normal or vice versa, compromising diagnosis reliability.

Differences in Contrast Reproduction between Electronic Devices for Visual Assessment: Clinical Implications

“…Comparisons between different devices with different screen characteristics have been previously reported [15,20,22], including even comparisons between devices with the same screen (with the same characteristics) [16,29]. In the present study, not only were the compared devices the same, but they were also from the same year of production (2019) and the same fabrication batch (with correlative serial numbers).…”

“…The problem of screen reproduction is critical when using the devices for luminancebased measurements but is even more critical when analyzing the response to a chromatic stimulus as demonstrated in previous studies [15,16]. In this study, we focused only on luminance characterization of the devices, and therefore achromatic stimuli were measured.…”

“…In the case of programs that can be downloaded to different devices, however, do we really know what they are reproducing? The type of display or the characteristics of the graphics card can widely alter the reproduction of a given stimulus, even when environmental and ergonomic conditions are under control [15,16]. Differences in reproduction should be taken into consideration by the vision specialists as a potential clinical limitation but also by the manufacturers and designers as a technological challenge [17].…”

“…The problem of cross-reproduction between different devices has been also studied by many authors [15,20,22]. Even comparison between devices with the same type of screen has demonstrated that the reproduction of an achromatic or a chromatic stimulus in different devices cannot be simply performed [16,29]. The aim of the present study was to evaluate differences in luminance reproduction between devices from the same model, year of fabrication and manufacturing batch to determine if a global characterization based on a generic device is a feasible solution to ensure the correct cross-reproduction for an achromatic stimulus, or otherwise, individual luminance characterization should be performed on each device.…”

ColourSpot, a novel gamified tablet-based test for accurate diagnosis of color vision deficiency in young children

“…One potential solution to the limited accessibility of pediatric tests for CVD is to use tablet-based methods. Such methods can provide mass testing at home, school and in the community, and are colorimetrically adequate for color vision testing if properly calibrated (Bodduluri, Boon, & Dain, 2017a;Dain & Almerdef, 2016;de Fez et al, 2016;de Fez, Luque, García-Domene, et al, 2018a). Two iPad-based tests for CVD in children, the DoDo game (Nguyen, Do, et al, 2014a;Nguyen, Lu, et al, 2014b) and the Optopad (de Fez, Luque, Matea, et al, 2018b), have been recently developed.…”