Abstract
Purpose :
Short viewing distances during near tasks are known to be a risk factor for myopia development. This prospective study aimed to compare viewing distances measured by two wearable sensors, the Vivior and Clouclip, in a laboratory setting for different near tasks.
Methods :
In the first phase, the Vivior and Clouclip were attached to the right side of a spectacle frame on a mannequin head placed in front of a computer desktop monitor. The mannequin head was placed between 10 to 100 cm from the monitor (in 5 cm increments) and viewing distances were measured with each sensor. In the second phase, 13 participants aged between 18 to 35 years were asked to wear the Vivior or Clouclip attached simultaneously to the right side of a spectacle frame. Participants performed four 20-minute duration near tasks in random order: read printed text, read digital text on an iPad, type on a laptop and watch videos on an iPad. Viewing distances during each near task were measured by the sensors under three different ambient illuminations: 500 lux, 250 lux and 25 lux. Viewing distances were also measured manually with a ruler in both study phases.
Results :
In the first phase, Bland-Altman analysis of viewing distance measured manually versus Vivior and manually versus Clouclip showed a mean difference of -0.22 ± 0.57 cm [Limits of agreement (LOA) -1.36 to +0.92 cm] and -0.27 ± 0.92 cm [LOA -2.08 to +1.54 cm], respectively. In the second phase, two-way ANOVA [F(4, 108) = 0.04, p = 0.9] and Tukey’s multiple comparisons (p ≥ 0.9 for all) showed mean differences in viewing distances captured in adults were not significantly different between manual versus Vivior (range of differences -0.32 to 1.94 cm) or Clouclip measurements (range of differences -0.25 to 1.61 cm), and between Clouclip and Vivior (range of differences 0.43 to 3.38 cm) during any of the four near tasks under three different ambient illuminations.
Conclusions :
Both Vivior and Clouclip showed good agreement in measuring viewing distances. There was no significant difference in viewing distances measured with the Vivior, Clouclip and manually during the four near tasks in adults. Vivior and Clouclip can be used to measure habitual viewing distances in myopic children to understand better the impact of near tasks on myopia development or progression.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.