Validation of the Symptom Questionnaire for Visual Dysfunctions (SQVD): A Questionnaire to Evaluate Symptoms of any Type of Visual Dysfunctions

Effects of colour and scene dynamism on visual fatigue in animated films

Animated films are highly popular in society, particularly among children and adolescents. During film production, selecting an adequate colour palette and scene dynamism is crucial for creating a visual impact on the audience. However, the influence of visual aesthetics, such as colour and scene dynamism on visual fatigue remains unexplored. In the present study, visual fatigue was assessed and compared in 30 young participants after viewing two popular films: Spider-Man: Across the Spider-Verse, an active, fast-paced film, and My Neighbour Totoro, a more relaxed film. Both films were viewed twice, once with the original colour palette and once in greyscale. Watching Spider-Man film induced a greater degree of visual fatigue than My Neighbour Totoro in two subjective questionnaires evaluating visual fatigue, and in the vergence facility and binocular accommodative facility tests. Moreover, important differences in the visual dynamics and colour aspects between both films were found. These results demonstrate that the high-paced and high-colour aspects of films directly affect visual fatigue. Future animated film producers should consider these factors that are relevant to their audiences.

Linguistic and cultural validation of symptom questionnaire for visual dysfunctions (SQVD) for psychometric analysis in the Chinese context

The Spanish scale symptom questionnaire for visual dysfunctions (SQVD) was sinicized and tested for reliability and validity in the Chinese context, employing both classical measurement theory and item response theory. A meticulous translation was conducted using the modified Brislin translation model, with input from experts for cross-cultural debugging and in-depth review. Following a pre-survey study, the Chinese version of the SQVD was finalized. A convenience sampling method was used to select 270 patients from the target group and 252 valid questionnaires were successfully collected. The Rasch model was employed to assess response category functionality, fit statistics, unidimensionality, person and item reliability, separation, targeting, and differential item functioning. Classical test theory was applied to evaluate internal consistency and retest reliability, supplemented by correlation analysis. Job characteristic curves were also plotted to assess diagnostic accuracy. The Chinese SQVD conformed to a unidimensional structure with excellent reliability and validity. Person and item reliabilities were 0.85 and 0.99, respectively, indicating, high stability. Person and item separation indices were 2.37 and 11.54, respectively, signifying strong differentiation ability. Retest reliability was 0.917, further emphasizing the stability of the scale. The area under the receiver operating characteristic curve was 0.908 (95% CI: 0.854, 0.962), with a cutoff value of 7.5 and Youden index of 0.733, highlighting the scale's high diagnostic accuracy. The translated and culturally adapted Chinese SQVD demonstrated excellent psychometric properties. With streamlined items, short assessment time, and high efficiency, the scale is a stable and reliable clinical tool for detecting a variety of conditions related to refractive, regulatory, and binocular vision dysfunction.

Evaluation and application of a Chinese version symptom questionnaire for visual dysfunctions (CSQVD) in school-age children

Objective

To develop and evaluate a Chinese version of the Symptom Questionnaire for Visual Dysfunctions (CSQVD) to quantify visual dysfunction symptoms in school-age children with various eye diseases, and to explore the relationship between ophthalmological disorders and visual dysfunction symptoms.

Methods

Following standard scale adaptation procedures, the Symptom Questionnaire for Visual Dysfunctions (SQVD) was translated into Chinese (CSQVD). We employed random sampling to survey 198 outpatients aged 7-18 to assess the psychometric properties of the CSQVD. Using the reliable and validated questionnaire, we evaluated the determinants of visual dysfunction symptoms among 406 school-age patients at an eye center. The CSQVD scores were correlated with demographic and clinical variables, including gender, age, eye position, refractive power, and best-corrected visual acuity. Univariate analysis identified potential risk factors, followed by binary logistic regression and multiple linear regression analysis on factors with a P-value <0.05.

Results

The CSQVD scale's critical ratio (CR) values ranged from 6.028 to 10.604. The Cronbach's Alpha coefficient was 0.779, and Spearman-Brown split-half reliability was also 0.779. The I-CVI varied from 0.83 to 1.000, the S-CVI/Ave was 0.857, and the KMO value was 0.821. Multifactorial regression analysis indicated that high myopia (OR ​= ​5.744, 95% CI [1.632, 20.218], P ​= ​0.006) and amblyopia (OR ​= ​9.302, 95% CI [1.878, 46.058], P ​= ​0.006) were significant predictors of CSQVD symptoms. Multiple linear regression analysis showed that BCVA of amblyopic eyes (B ​= ​-5.052, 95% CI [-7.779, 2.325], P ​= ​0.000) and SE power (B ​= ​-0.234, 95% CI [-0.375, 0.205], P ​= ​0.001) significantly affected the CSQVD scale scores.

Conclusions

The Chinese version of the SQVD scale (CSQVD) demonstrates good feasibility, discriminatory power, validity, and reliability in assessing Chinese school-aged children. Furthermore, those who have severe myopia and amblyopia reported more visual dysfunction symptoms.

Assessing the role of visual dysfunctions in the association between visual symptomatology and the use of digital devices

PURPOSE

To evaluate the association between visual symptoms and use of digital devices considering the presence of visual dysfunctions.

METHODS

An optometric examination was conducted in a clinical sample of 346 patients to diagnose any type of visual anomaly. Visual symptoms were collected using the validated SQVD questionnaire. A threshold of 6 hours per day was used to quantify the effects of digital device usage and patients were divided into two groups: under and above of 35 years old. A multivariate logistic regression was employed to investigate the association between digital device use and symptoms, with visual dysfunctions considered as a confounding variable. Crude and the adjusted odds ratio (OR) were calculated for each variable.

RESULTS

57.02 % of the subjects reported visual symptoms, and 65.02% exhibited some form of visual dysfunction. For patients under 35 years old, an association was found between having visual symptoms and digital device use (OR = 2.10, p = 0.01). However, after adjusting for visual dysfunctions, this association disappeared (OR = 1.44, p = 0.27) and the association was instead between symptoms and refractive dysfunction (OR = 6.52, p < 0.001), accommodative (OR = 10.47, p < 0.001), binocular (OR = 6.68, p < 0.001) and accommodative plus binocular dysfunctions (OR = 46.84, p < 0.001). Among patients over 35 years old, no association was found between symptoms and the use of digital devices (OR = 1.27, p = 0.49) but there was an association between symptoms and refractive dysfunction (OR = 3.54, p = 0.001).

CONCLUSIONS

Visual symptoms are not dependent on the duration of digital device use but rather on the presence of any type of visual dysfunction: refractive, accommodative and/or binocular one, which should be diagnosed.

Comparison of two visual-verbal tests of ocular motility using an eye-tracker

PURPOSE

This study aims to compare eye movements monitored with an eye tracker during two visuo-verbal tests for assessing ocular motility. The study explores the potential of digital assessment and eye tracking technology in enhancing the understanding of ocular motility during these tests.

METHODS

47 healthy participants were included (20 males, 27 females), with a mean age of 21.34±1.77 years. The participants underwent optometric examinations to ensure visual health and exclude any dysfunctions or pathologies. The experimental protocol involved the digitized versions of the DEM and King-Devick tests, monitored with an eye tracker.

RESULTS

The vertical subtests of DEM test showed fewer saccades, longer fixation durations, smaller saccade amplitudes, and slower saccade speeds compared to the horizontal subtest. The King-Devick test exhibited comparable fixation and saccade numbers, while fixation duration slightly increased with test difficulty. Statistically significant differences were found between the tests, but a positive correlation was observed.

CONCLUSIONS

Statistically significant differences were observed between the DEM and King-Devick tests, indicating that they measure similar aspects but are not interchangeable. The DEM test offers more comprehensive information with vertical saccade assessment. Test duration correlates positively with saccade and fixation count, fixation duration, and saccade speed.

Development and Validation of the Life for Low Vision Questionnaire (LIFE4LVQ) Using Rasch Analysis: A Questionnaire Evaluating Ability and Independence

Low vision (LV) has a substantial impact on an individual’s daily functionality and patient-reported outcome measures (PROMs) are increasingly incorporated into the evaluation of this problem. The objective of this study was to describe the design of the new “Life for Low Vision Questionnaire (LIFE4LVQ)”, as a measure of daily functionality in LV and to explore its psychometric properties. A total of 294 participants completed the LIFE4LVQ and the data were subjected to Rasch analysis to determine the psychometric properties of the questionnaire, including response category ordering, item fit statistics, principal component analysis, precision, differential item functioning, and targeting. Test–retest reliability was evaluated with an interval of three weeks and intraclass correlation coefficients (ICC) were used. The correlation between the questionnaire score and Best Corrected Visual Acuity (BCVA) was examined using Spearman’s correlation coefficient. Rasch analysis revealed that for most items the infit and outfit mean square fit values were close to 1, both for the whole scale and its subscales (ability and independence). The separation index for person measures was 5.18 with a reliability of 0.96, indicating good discriminant ability and adequate model fit. Five response categories were found for all items. The ICC was 0.96 (p < 0.001; 95% CI, 0.93–0.98), suggesting excellent repeatability of the measure. Poorer BCVA was significantly associated with worse scores (rho = 0.559, p < 0.001), indicating excellent convergent validity. The functional, 40-item LIFE4LVQ proved to be a reliable and valid tool that effectively measures the impact of LV on ability and independence.