Performance of a new device for the clinical determination of light discomfort

Abstract

Purpose: To assess the performance of a new device for the clinical determination of light discomfort on a large sample of healthy human subjects. Methods: A total of 489 subjects ranging from 20 to 70 years old (241 men, 248 women) were evaluated with the LUMIZ™ 100 to determine light discomfort. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (CoV), and intraclass correlation coefficient (ICC). Repeated measures ANOVA, Kruskal-Wallis, and correlation analysis were applied to test for differences between repeated measures, and effect of age on reliability. Results: Discomfort thresholds obtained are well distributed across the light intensity range available (25 to 10211 lux). Intrasession ICCs are higher than 0.849 for all thresholds, and 85% of CoV are below 10%. Thresholds obtained in the first set of measurements are highly correlated with the median of three sets (r2 > 0.8). Intersession, 64% of CoV are below 10%. Age does not affect discomfort thresholds (p = 0.30), nor affect reliability (variance on CoV, p = 0.368) Conclusions: The new device provides good intrasession repeatability for the clinical determination of light discomfort thresholds, although variance is slightly greater between sessions. The system is useful for the clinical determination of light discomfort.

Comparison of questionnaire items for discomfort glare studies in daylit spaces

“…Although there are some devices used in clinical determinations of individuals' discomfort glare through electromyograms, 66 or to measure an individual's sensitivity to discomfort glare, 67 these objective methods are usually considered invasive with the attachments of electrodes around the eye in the former or cover the entire field of view in the latter. Physiological and ocular data such as pupil diameter, pupil unrest index, and eye fixation rate were also found to correlate with glare stimuli 67 but no thresholds to describe glare degree were derived. Artificial intelligence has also been trained to predict if the occupant experiences discomfort glare.…”

Evaluation of Physiological Parameters on Discomfort Glare Thresholds Using LUMIZ 100 Tool

“…The acquisition protocol and reliability of measurements have been previously described in detail elsewhere. 5 Light sensitivity is computed using a mean of six logarithmic illumination thresholds.…”

“…4 In a healthy population, there is a large range of discomfort thresholds and light sensitivity. 5 In the scientific literature, some physiological factors have been considered to better understand this variability within a healthy population.…”