Table of Contents
Abstract
The Computer Vision Syndrome Questionnaire (CVS-Q) is a specialized psychometric instrument designed to systematically evaluate the ocular and visual symptoms associated with prolonged digital screen exposure. As modern workplaces increasingly rely on digital infrastructure, occupational health professionals require robust tools to quantify the physiological toll of screen time, commonly referred to as Digital Eye Strain. The Persian adaptation of this tool (CVS-Q FA) represents a critical methodological advancement for assessing this modern occupational hazard within the Iranian population, providing a standardized metric where previously only ad hoc, unvalidated surveys were utilized.
The adaptation process of the CVS-Q FA underscores the importance of rigorous cross-cultural translation in psychometrics. Rather than merely translating words, the developers utilized established international guidelines to ensure conceptual equivalence, meaning the psychological and physiological experiences of eye strain were accurately captured in the target cultural context. This involved iterative forward and backward translations, expert committee reviews, and cognitive debriefing with target users to ensure high comprehensibility and clinical utility.
Ultimately, the CVS-Q FA functions as a highly effective diagnostic and research tool. By measuring both the frequency and intensity of 16 distinct symptoms, it generates a composite severity score that can reliably distinguish between individuals with and without clinical levels of Computer Vision Syndrome. Its strong psychometric properties make it an invaluable asset for epidemiologists tracking occupational health trends, clinicians diagnosing Digital Eye Strain, and researchers evaluating ergonomic or medical interventions in the workplace.
📊 Psychometric Scorecard
16
Unidimensional
0.80
📍 Iran
Authors
Purpose
The primary objective of the CVS-Q FA is to provide a standardized, culturally adapted, and psychometrically sound measure of Computer Vision Syndrome for Persian-speaking populations. With the exponential rise in digital device usage—accelerated further by shifts toward telecommuting—Digital Eye Strain has emerged as a pervasive public health issue. However, epidemiological research in this area has historically been hampered by the use of inconsistent, non-validated questionnaires, leading to wildly fluctuating prevalence estimates.
This instrument addresses a significant methodological gap by offering a validated diagnostic threshold. For occupational health researchers, it enables accurate prevalence tracking and the evaluation of workplace ergonomic interventions. For clinicians, it provides a quick, self-administered screening tool to quantify symptom severity, guiding treatment decisions for patients suffering from screen-related visual discomfort.
Construct
Computer Vision Syndrome (CVS), also known as Digital Eye Strain, is a multidimensional physiological and perceptual construct encompassing a cluster of ocular, visual, and musculoskeletal symptoms resulting from prolonged use of digital displays. The theoretical framework underlying the CVS-Q conceptualizes this syndrome not as a single isolated symptom, but as a cumulative burden of various interconnected visual disturbances. These include asthenopia (eyestrain), ocular surface mechanisms (dryness, burning, redness), and visual acuity issues (blurriness, double vision).
Psychometrically, the CVS-Q FA treats this construct as unidimensional, meaning that while the symptoms vary in their specific physiological manifestations, they all contribute to a single underlying latent variable: the overall severity of Digital Eye Strain. The instrument captures this construct by evaluating two critical dimensions of the patient's experience: the frequency of symptom occurrence and the intensity of the discomfort. This dual-axis approach ensures a more nuanced and accurate representation of the syndrome's impact on daily functioning than measuring frequency or intensity alone.
Validity
The validation framework for the CVS-Q FA demonstrates exceptional rigor, establishing strong evidence for both content and criterion validity. Content validity was secured through a panel of 15 optometry experts, yielding a highly robust Scale-Level Content Validity Index (S-CVI) of 0.92. At the item level, all components achieved an index above 0.80 after minor linguistic adjustments, ensuring that every question is highly relevant to the target construct in the Persian language.
From a diagnostic perspective, the criterion validity of the instrument is particularly strong. Receiver Operating Characteristic (ROC) analysis revealed that the scale possesses a sensitivity of 81.1% and a specificity of 69.2%. In practical clinical terms, this means the questionnaire is highly capable of correctly identifying individuals who genuinely suffer from Computer Vision Syndrome (low false-negative rate), while maintaining an acceptable ability to rule out those who do not. These metrics align closely with the original Spanish version, confirming the tool's cross-cultural diagnostic stability.
Reliability
The reliability profile of the CVS-Q FA indicates that it is a highly consistent and stable measurement tool. Internal consistency, which evaluates how well the 16 items correlate with one another to measure the same underlying construct, was strong, evidenced by a Cronbach's alpha coefficient of 0.80. This value sits comfortably within the optimal range for clinical and research tools, indicating excellent cohesion without redundant item overlap.
Furthermore, the instrument demonstrated robust temporal stability. When administered to a subset of participants on two separate occasions, the test-retest reliability yielded an Intraclass Correlation Coefficient (ICC) of 0.81 and a Cohen's kappa of 0.65. These metrics confirm that the questionnaire is not overly sensitive to transient daily fluctuations and can reliably measure a patient's baseline symptom severity over time, making it highly suitable for longitudinal studies evaluating the efficacy of workplace interventions.
Factor Analysis
The structural validity of the CVS-Q FA was evaluated to ensure that the translated items behave statistically similarly to the original instrument. The researchers utilized factor analysis to examine the underlying latent structure of the 16 symptom items. The analytical approach confirmed that the scale maintains a strictly unidimensional structure, meaning all items successfully load onto a single overarching factor representing Computer Vision Syndrome.
This finding is crucial for scoring and interpretation. Because the scale is unidimensional, researchers and clinicians are justified in calculating a single total severity score rather than having to compute multiple subscale scores. The analysis demonstrated robust goodness-of-fit statistics, indicating that the theoretical model of a single underlying syndrome perfectly matches the actual response patterns of the Persian-speaking sample. No items needed to be removed, preserving the comprehensive nature of the original tool.
Instrument
| Test Type | Self-report questionnaire |
| Format | 16 items assessing frequency (never, occasionally, often/always) and intensity (moderate, intense) |
| Scoring | Frequency and intensity responses are recoded and combined to calculate a severity score for each symptom. These are summed to yield a total score. A total score >= 6 indicates the presence of CVS. |
| Language | Persian |
| Population | Adults, Employees, Students |
| Administration | Self-administered |
Scoring & Interpretation Guidelines
| Scoring Instructions | For each of the 16 symptoms, frequency and intensity are evaluated. These two parameters are recoded into a single severity value per symptom, which are then summed to create the total scale score. |
| Cut-off Scores | Total score >= 6 indicates presence of Computer Vision Syndrome |
Computer Vision Syndrome Questionnaire – Persian Version Items
Items are currently not available
The individual items of this scale are not publicly available. Researchers interested in using this instrument should contact the original authors directly to request the scale materials.
Sample
The validation sample consisted of 102 computer users, specifically university staff and graduate Students who regularly use digital devices in their workplace. Additional samples included 20 participants for the pretest, 7 for cognitive debriefing, 46 for test-retest reliability, and an expert committee of 15 optometrists.
Cite This Paper
Milad Qolami, Ali Mirzajani, Elena Ronda-Pérez, Natalia Cantó-Sancho, Mar Seguí-Crespo (2022). Computer Vision Syndrome Questionnaire – Persian Version. International ophthalmology. https://doi.org/10.1007/s10792-022-02340-3
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Cite this article
Mohammed looti (2026). Computer Vision Syndrome Questionnaire – Persian Version. PSYCHOLOGICAL SCALES. Retrieved from https://scales.arabpsychology.com/s/computer-vision-syndrome-questionnaire-persian-version/
Mohammed looti. "Computer Vision Syndrome Questionnaire – Persian Version." PSYCHOLOGICAL SCALES, 14 Aug. 2026, https://scales.arabpsychology.com/s/computer-vision-syndrome-questionnaire-persian-version/.
Mohammed looti. "Computer Vision Syndrome Questionnaire – Persian Version." PSYCHOLOGICAL SCALES, 2026. https://scales.arabpsychology.com/s/computer-vision-syndrome-questionnaire-persian-version/.
Mohammed looti (2026) 'Computer Vision Syndrome Questionnaire – Persian Version', PSYCHOLOGICAL SCALES. Available at: https://scales.arabpsychology.com/s/computer-vision-syndrome-questionnaire-persian-version/.
[1] Mohammed looti, "Computer Vision Syndrome Questionnaire – Persian Version," PSYCHOLOGICAL SCALES, vol. X, no. Y, ص Z-Z, August, 2026.
Mohammed looti. Computer Vision Syndrome Questionnaire – Persian Version. PSYCHOLOGICAL SCALES. 2026;vol(issue):pages.