
==== Front
Sci Rep
Sci Rep
Scientific Reports
2045-2322
Nature Publishing Group UK London

70821
10.1038/s41598-024-70821-9
Article
CVS-Q teen: an adapted, reliable and validated tool to assess computer vision syndrome in adolescents
Seguí-Crespo Mar 12
Cantó-Sancho Natalia 1
Sánchez-Brau Mar mdmsb7@gmail.com

1
Ronda-Pérez Elena 13
1 https://ror.org/05t8bcz72 grid.5268.9 0000 0001 2168 1800 Public Health Research Group, University of Alicante, San Vicente del Raspeig, Spain
2 https://ror.org/05t8bcz72 grid.5268.9 0000 0001 2168 1800 Department of Optics, Pharmacology and Anatomy, University of Alicante, San Vicente del Raspeig, Spain
3 grid.466571.7 0000 0004 1756 6246 Biomedical Research Networking Center for Epidemiology and Public Health (CIBERESP), Madrid, Spain
16 9 2024
16 9 2024
2024
14 2157627 3 2024
21 8 2024
© The Author(s) 2024
2024
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Adolescents’ extensive use of digital devices raises significant concerns about their visual health. This study aimed to adapt and validate the computer vision syndrome questionnaire (CVS-Q©) for adolescents aged 12–17 years. A mixed-method sequential design was used. First, a qualitative study was involved two nominal groups to assess the instrument’s acceptability. A subsequent cross-sectional quantitative study with 277 randomly selected adolescents assessed reliability and validity. Participants completed the adapted CVS-Q©, an ad hoc questionnaire, and the ocular surface disease index (OSDI) questionnaire. Repeatability was tested in 54 adolescents after 7–14 days. The Rasch-Andrich rating scale model was used. Instructions and symptoms were modified to obtain the 14-item CVS-Q teen©. It showed unidimensionality, no local dependence between items, and respected monotonicity. Adequate internal consistency (person reliability = 0.69, item reliability = 0.98) and intraobserver reliability (intraclass correlation coefficient = 0.77, Cohen's Kappa = 0.49) were observed. A significant correlation (0.782, p < 0.001) between CVS-Q teen© and OSDI supported construct validity. A score of ≥ 6 points indicated computer vision syndrome (CVS) (sensitivity = 85.2%, specificity = 76.5%, and area under the curve = 0.879). In conclusion, CVS-Q teen© is a valid and reliable instrument for assessing CVS in adolescents using digital devices, applicable in research and clinical practice for early identification and recommendations for visual health.

Keywords

Adolescent
Computer vision syndrome
Questionnaire
Digital devices
Psychometrics
Validation study
Subject terms

Eye manifestations
Eye diseases
Paediatrics
Public health
Quality of life
Paediatric research
http://dx.doi.org/10.13039/501100004587 Instituto de Salud Carlos III PI20/01629 issue-copyright-statement© Springer Nature Limited 2024
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pmcIntroduction

The new information and communication technologies (NICTs) have spread worldwide in recent years, particularly among children and adolescents. 93.1% of people aged 10–15 years use a computer, 94.9% use the Internet and 69.5% have a smartphone1.

One of the health problems that results from prolonged use of digital devices is computer vision syndrome (CVS), which is defined as a group of problems related to eyes and vision2. These symptoms arise when demands exceed visual capabilities. Digital device use involves intense visual strain with continuous accommodation and convergence adjustments, leading to more symptoms in individuals with oculomotor anomalies or uncorrected refractive errors3. It also reduces blink frequency and amplitude which can cause ocular surface problems4. It has been observed that using electronic devices leads to an increase in incomplete blinks5. Also, CVS increases in those who have been using digital devices for more years6 and more hours of daily use7.

Most studies on CVS focus on working populations8–10 and some on university students11–13. CVS prevalence ranges from 50.0 to 70.0% in workers8,9, and can reach up to 90.0% among university students11. A literature review identified 10 studies on CVS in adolescents, all published in the last 6 years, mainly in Asia14–23. Reported prevalence ranges from 12.014 to 93.0%23. These studies used ad hoc questionnaires15–17,22, non-specific CVS tools19, or instruments designed and validated for adults or in other languages without prior adaptation and validation for adolescent14,18,20,21,23. Other studies have linked increased myopia and dry eye in children with time spent on computer games, mobile phones, and reduced outdoor activities24,25. Longer digital device use correlates with more severe CVS in adolescents21. Excessive use also contributes to sleep problems, anxiety, lack of social interaction, and depression, impacting health, development, and academic performance26.

Children and adolescents are more susceptible to visual problems due to patterns of use such as not taking breaks, inappropriate distances, and inadequate lighting2,27. These age groups are more vulnerable to excessive use of digital devices due to lack of self-control, entertainment, influence from family and friends, and academic tasks27. Educational centres’ increasing involvement with educational technologies has heightened this exposure. Technologies can enhance instruction quality by redistributing resources, increasing chances to practise, supplementing instructional time, and personalising instruction. They also engage and support learners by varying content representation, stimulating interaction, and prompting collaboration28. Thus, studies are needed that reflect the realities of schools, considering different exposure characteristics and demand periods.

In 2015 the computer vision syndrome questionnaire (CVS-Q©) was designed and validated in Spanish to assess CVS in adults29. It is a patient reported outcome measure (PROM), a questionnaire that collects ocular and visual symptoms directly from the people who experience them30. It has been used in different adult populations8,13,31 and translated, culturally adapted and validated in multiple languages32,33. However, there is no validated questionnaire for adolescents. Instruments for this age group need comprehensible terminology, symptomatology relevant to this population, ease of completion, and demonstrated validity and reliability. The aim of this study is to adapt and validate the CVS-Q© for adolescents aged 12 to 17 years.

Methods

The following research is based on the protocol published by Seguí-Crespo et al.34, which in turn was carried out following the guide for the adaptation and validation of health questionnaires by Ramada-Rodilla et al.35, except for the translation section, as the language is the same as that of the original questionnaire.

A mixed method sequential design was used. The process consisted of two phases, which in turn were subdivided into 6 steps in total (Fig. 1). In the first phase, qualitative data collection activities were conducted to adapt and assess the content and face validity of the instrument. In the second phase, quantitative data collection activities were conducted to assess the reliability, criterion and construct validity of the instrument through a cross-sectional study.Fig. 1 Methodological development followed in obtaining the CVS-Q teen© for use with adolescents between 12 and 17 years of age.

Qualitative phase

The nominal group technique was applied in two groups: one formed by 8 adolescents between 12 and 17 years of age (4 females and 4 males) selected by convenience from different schools, and the other formed by 10 key informants.

Step 1: adaptation

In the first meeting, the 8 adolescents filled in the CVS-Q© and an analysis of its comprehensibility was carried out by means of an ad hoc questionnaire (terminology used, whether the instructions were understandable), and they also proposed changes and suggestions. Once these changes were incorporated into the original questionnaire, the V1 version of the adapted CVS-Q© was created.

Step 2: content validity

In the second meeting, V1 was presented to 4 eye care professionals (ophthalmologists and opticians-optometrists), 3 teachers and 3 parents of adolescents. As in step 1, they made the contributions they considered from their perspective. From this process, the V2 version of the adapted CVS-Q© was created.

Step 3: apparent validity

A pilot study was conducted with 31 adolescents between 12 and 17 years of age to confirm the quality of the adaptation and to verify practical aspects of its application. The sample was selected by non-probability snowball sampling. Participants completed V2 of the CVS-Q© and an ad hoc questionnaire that included socio-demographic data, questions about the comprehensibility of the instructions and symptoms, whether to add or remove any symptom, about the difficulty of the structure of the questionnaire and the way of answering, and about the possibility of improving any other aspect. Once the instructions, symptoms and response options had been reviewed, the acceptability of the instrument was measured through a qualitative analysis by grouping common discourses. According to the literature, it was considered inadequate if more than 15% of participants expressed difficulties or suggested changes35. This resulted in the V3 version of the adapted CVS-Q©.

Quantitative phase

To validate V3, a cross-sectional study was conducted in 277 adolescents36, aged 12–17 years of age, randomly selected from 2 public schools and 1 subsidised school (A, B and C respectively), two of which used printed textbooks and one digital textbook. All completed V3 of the CVS-Q© and an ad hoc questionnaire with socio-demographic information (sex, age), academic information (educational institution, year and textbooks), and their use of digital devices for studying. In addition, they underwent a visual examination, which included visual acuity in mono and binocular distance vision, cover/uncover test, Hirschberg reflex and eye movements. Students who did not achieve a monocular visual acuity of 0.0 logMAR or who had any manifest ocular alteration (such as ocular pathology or the presence of tropia) were excluded from the study. In total, 15 adolescents were excluded: 8 did not achieve 0.0 logMAR visual acuity with their usual optical compensation and 7 had strabismus. The adolescents included in the study had a monocular visual acuity of 0.06 ± 0.05 logMAR in the right eye, 0.06 ± 0.04 logMAR in the left eye, and 0.07 ± 0.04 logMAR binocularly. All participants demonstrated a normal Hirschberg reflex and eye movements.

Step 4: construct validity and internal consistency

The basic Rasch-Andrich rating scale model, the rating scale model (RSM)37, was used and the following properties were assessed:Item and person fit to the predictions of the Rasch model. This was assessed using the mean squares (MNSQ) infit and outfit statistics; a range between 0.60 and 1.40 suggests a good fit37. Outfit MNSQ values > 2.00 should be dropped as they indicate inaccurate measurement37.

Item polarity. Assessed by inter-item correlations. These should be positive and away from 0 (or, alternatively, the observed correlation should be similar to the expected one), which will confirm that it is not necessary to eliminate any item.

Empirical measure of item category. Monotonicity is assessed if all response categories are represented for each item and classified according to their level of severity.

Performance of the rating scale. It is assessed whether between the different thresholds of the response probability curves there is a minimum separation of 1.40 logits37. In the case of the CVS-Q© there are two severity thresholds, a threshold between categories 0 and 1 and a threshold between categories 1 and 2.

Dimensionality of the questionnaire and local dependence of the items. Dimensionality is assessed using principal component analysis of Rasch residuals. For unidimensionality to exist, the variance unexplained by the first contrast must be < 10.0% and the eigenvalue of the first contrast must be < 1.90. The Yen-Q3 statistic was calculated to assess the local independence of the items. Any residual correlation with a value higher than 0.20 of the mean correlation could indicate local dependence38.

Measurement error. The information function of the questionnaire (and its reciprocal, the standard error measurement, SEM) is generated. This function describes the variation of the accuracy of the questionnaire along the latent trait and allows us to know the areas of highest accuracy of the instrument.

Internal consistency and person-item separation index. An internal consistency for persons ≥ 0.7039 is considered good and for items it should be > 0.9040. The person separation index should be > 2.00 logits for persons and > 3.00 logits for items.

Targeting. The appropriateness of the severity level of the items to the sample is assessed. A good alignment between items and persons occurs when the mean scores of the persons are close to 0 logits. A difference of more than 1 logit may indicate poor targeting41.

Analysis of differential item functioning (DIF) and its impact on questionnaire scores. This assesses whether the way in which items define a measurement scale is the same for different groups37. It was analysed according to sex, academic year, school and textbook. An item was considered to have DIF if the between-group contrast (DIF size) was > 0.64 and the t-Rasch-Welch test value was significant at the 0.05 level after Bonferroni correction37. The proportion of estimates that differed by > 0.50 logits was calculated as an indicator of the impact of DIF on the scores.

In addition, to further investigate construct validity, a convergent validity study was conducted using the ocular surface disease index (OSDI) questionnaire, as it has some items similar to those of the CVS related to dry eye42. After testing for normality, we analysed the difference in the scores obtained between the two questionnaires (Student's t-test) and the difference in the prevalence of CVS (Chi-square) in adolescents with and without dry eye symptoms.

Step 5: test–retest reliability

Between 7 and 14 days after the first measurement, a random subsample of 54 adolescents completed the adapted CVS-Q© V3 again. The intraclass correlation coefficient (ICC) based on a mixed-effects model with a measure of absolute agreement was calculated for questionnaire scores, and Cohen's Kappa Index (k), with a corresponding 95% confidence interval (95%CI), was calculated for differences in CVS diagnosis. The acceptable level of ICC is ≥ 0.7039 and for k a ≤ 0 was considered as indicating no agreement, 0.01–0.20 as none to slight, 0.21–0.40 as fair, 0.41- 0.60 as moderate, 0.61–0.80 as substantial, and 0.81–1.00 as almost perfect agreement43. In addition, mean scores were compared between the two administrations (Student’s t-test for paired data).

Step 6: criterion validity

The same criterion used by the authors of the original questionnaire "occurrence of at least one symptom two or three times a week" was used to define the presence of CVS29. Sensitivity and specificity were calculated, allowing the receiver operating characteristic (ROC) curve to determine the diagnostic performance of the questionnaire and the cut-off point or score from which to consider the adolescent symptomatic.

The statistical programmes SPSS version 28, Winsteps version 5.2.5.1 and Jamovi 2.2.5 were used to perform the analyses.

Ethics declaration

This study was approved by the Research Ethics Committee of the University of Alicante (UA-2020-01-13). It has been conducted in accordance with Good Clinical Practice standards and the applicable international ethical principles for human research, as per the latest revision of the Helsinki Declaration. The data collected in the study have been processed in accordance with the current legislation on date protection. All students who participated in each phase were provided with a written participant information sheet, and the signature of informed consent was sought from the students and, depending on their age, from their parents/guardians.

Results

Qualitative phase

All the partial modifications of the symptoms that were introduced by the two nominal groups consulted and as a result of the pilot study can be consulted in Supplementary Table S1 online. The instructions were also modified and adapted to the proposals made. In the pilot study, 96.8% of the adolescents found the instructions easy to understand. 74.2% indicated a good comprehension of the symptoms and 8 students reported difficulties in understanding a symptom, with "coloured halos around objects" being the most difficult (16.1%). This resulted in the adapted CVS-Q teen© questionnaire, which had 14 symptoms.

Quantitative phase

In the first RSM model it was observed that out of the total sample of 262 adolescents, 11 exceeded the cut-off value for outfit MNSQ (range: 2.15–3.67), so they were removed from the model and the analyses were repeated. In this second model the infit and outfit MNSQ values were within the established range (mean infit/outfit MNSQ = 0.99 ± 0.02). Therefore, the final sample included was n = 251 adolescents; its characteristics are reflected in Table 1.Table 1 Characteristics of the adolescents included in the analysis of reliability, construct and criterion validity.

Variable	n	%	
Total	251	100	
Sex	
 Male	115	45.8	
 Female	136	54.2	
Age (years)	
 12	23	9.2	
 13	32	12.7	
 14	44	17.5	
 15	70	27.9	
 16	51	20.3	
 17	31	12.4	
 Mean (SD) = 14.8 ± 1.5			
Educational institution	
 A	105	41.8	
 B	83	33.1	
 C	63	25.1	
Academic year	
 1st and 2nd CSE	74	29.5	
 3rd and 4th CSE	120	47.8	
 1st and 2nd BAC	57	22.7	
Textbooks	
 Printed books	65	25.9	
 Digital books	186	74.1	
Use of digital devices to study (hours/day)	
  < 4	109	43.4	
  ≥ 4	142	56.6	
 Mean (SD) = 4.3 ± 2.5			
SD standard deviation, CSE compulsory secondary education (12–16 years), BAC Baccalaureate.

The fit of the items to the predictions of the model was found to be within the established range (mean infit MNSQ = 1.01 ± 0.04 and mean outfit MNSQ = 0.99 ± 0.04). No negative correlations were observed between items (range: 0.28–0.60) and the expected correlation was very similar to the observed correlation for most items (Table 2). Item 14 (headache) is the symptom that adolescents perceive with the least severity and item 2 (gritty feeling in eye/eyes) as the most severe, followed by double vision (item 10). The questionnaire respected monotonicity for all items and, in addition, the three severity categories are represented and ordered (Supplementary Fig. S1 online).Table 2 Item Rasch analysis results of the symptom severity scale of CVS-Q teen©.

Item description	Severity	SE	Infit MNSQ	Outfit MNSQ	Item polarity	Observed correlation (%)	Expected correlation (%)	
1. Itchy eyes	 − 1.03	0.12	0.59	0.61	0.55	77.3	63.4	
2. Gritty feeling in eye/eyes	1.90	0.19	1.13	0.95	0.28	86.6	86.9	
3. Tearing	 − 0.22	0.13	0.90	0.96	0.38	64.0	65.1	
4. Excessive blinking	 − 0.20	0.13	1.12	1.17	0.39	59.1	65.1	
5. Eye redness	0.28	0.13	1.21	1.21	0.29	60.7	68.1	
6. Eye pain	0.14	0.13	1.01	0.98	0.43	66.8	66.8	
7. Heavy eyelids	 − 0.54	0.12	1.08	1.08	0.42	62.8	64.2	
8. Dry eye	0.13	0.13	1.05	0.99	0.49	67.2	66.7	
9. Blurred vision	 − 0.57	0.12	0.90	0.89	0.55	68.8	64.2	
10. Double vision	1.79	0.19	1.02	0.88	0.31	85.4	85.9	
11. Difficulty focusing	 − 0.42	0.12	0.95	0.93	0.54	67.6	64.2	
12. Increased sensitivity to ambient light	 − 0.25	0.13	1.15	1.16	0.46	59.9	65.0	
13. Lights around luminous objects	0.34	0.13	1.12	1.13	0.37	64.8	68.5	
14. Headache	 − 1.36	0.12	0.89	0.89	0.60	68.8	64.3	
SE standard error, MNSQ mean square.

The thresholds of the rating scale progressed monotonically, with a separation between thresholds of 3.14 logits (Fig. 2), as well as the mean scores per category (− 2.51, − 1.26 and − 0.21 for categories 0, 1 and 2, respectively). The infit and outfit values of the response categories were also good (infit: 0.99, 1.02 and 0.96; outfit: 0.99, 1.00 and 0.94; for response categories 0, 1 and 2, respectively).Fig. 2 Response probability curves by category for the CVS-Q teen©.

The first contrast had an eigenvalue of 1.70, and its proportion of unexplained variance was 8.7%, thus corroborating the unidimensionality of the questionnaire. The cut-off point for determining the local independence of the items was 0.299, the mean of the correlations being 0.099. In this case, no residual correlation exceeded this value, so local independence of all items is assumed.

The zone of highest accuracy of the CVS-Q teen© lies in the interval between − 0.73 (raw score = 11 points) and 1.20 logits (raw score = 19 points), with a SEM of 0.50 (Supplementary Fig. S2 online).

The internal consistency analysis showed a person separation reliability value of 0.69, an item reliability value of 0.98, and a person separation index of 1.49 logits and item reliability of 6.35 logits.

With respect to targeting, the mean of the individuals' scores was -1.90 (SD = 0.57). This indicates that the items express more severity than the severity expressed by individuals; the questionnaire lacks items at the lower levels of the latent trait (Fig. 3).Fig. 3 Wright map of the CVS-Q teen©.

Table 3 presents the results of the DIF analysis. There was no DIF according to course, school or whether the school used printed books or digital books. According to sex, item 5 (eye redness) showed DIF (DIF size = 1.30, t-Rasch-Welch < 0.004), although its impact on the questionnaire scores was low.Table 3 Differential item functioning (DIF) according to sex, academic year, educational institution and textbook used in the school.

Item description	DIF	DIF academic year	DIF educational institution	DIF	
Sex	1st/2nd vs 3rd/4th CSE	1st/2nd CSE vs 1st/2nd BAC	3rd/4th CSE vs 1st/2nd BAC	A vs B	A vs C	B vs C	Textbooks	
1. Itchy eyes	0.07	0.18	0.00	0.30	0.02	0.29	0.30	0.05	
2. Gritty feeling in eye/eyes	0.04	0.17	0.48	0.72	0.04	0.76	0.72	0.49	
3. Tearing	0.16	0.18	0.28	0.08	0.30	0.22	0.08	0.02	
4. Excessive blinking	0.33	0.51	0.33	0.30	0.33	0.03	0.30	0.25	
5. Eye redness	1.30*	0.15	0.30	0.68	0.28	0.96	0.68	0.27	
6. Eye pain	0.22	0.38	0.65	0.60	0.31	0.90	0.60	0.18	
7. Heavy eyelids	0.14	0.34	0.50	0.15	0.15	0.00	0.15	0.13	
8. Dry eye	0.39	0.44	0.00	0.05	0.03	0.08	0.05	0.05	
9. Blurred vision	0.22	0.25	0.37	0.12	0.09	0.03	0.12	0.41	
10. Double vision	0.23	0.16	0.62	0.53	0.46	0.99	0.53	0.36	
11. Difficulty focusing	0.26	0.37	0.17	0.01	0.30	0.31	0.01	0.29	
12. Increased sensitivity to ambient light	0.02	0.44	0.30	0.22	0.17	0.39	0.22	0.00	
13. Lights around luminous objects	0.02	0.24	0.51	0.26	0.13	0.13	0.26	0.47	
14. Headache	0.30	0.18	0.09	0.19	0.38	0.57	0.19	0.00	
CSE compulsory secondary education, BAC Baccalaureate.

*p < 0.004 (Bonferroni correction).

Convergent validity analysis showed a Spearman correlation coefficient 0.782 (p < 0.001). 37.3% of the adolescents had neither CVS nor dry eye symptoms, while 33.1% exceeded the cut-off point on both questionnaires. A significant association was observed between the variables "presence/absence of CVS" and "presence/absence of dry eye symptoms" (p < 0.001).

Test–retest reliability showed an ICC = 0.77 for the questionnaire scores, and a k = 0.49 for the diagnosis of CVS between both administrations; there was also no difference in the means of the questionnaires (p = 0.491).

The value that optimised both sensitivity and specificity was the cut-off point of − 2.06 logits, which is equivalent to a raw score of 6 points. With this cut-off point, the questionnaire has a sensitivity of 85.2%, a specificity of 76.5% and an area under the curve (AUC) of 0.879 with 95% CI 0.836–0.922 (Supplementary Fig. S3 online).

The CVS-Q teen©, presented in Supplementary Fig. S4 online (translated into English in Fig. S5), is a 14-symptom self-administered questionnaire asking the frequency and intensity of ocular and visual symptoms related to the use of digital devices in this population. The frequency and intensity data are recorded to calculate the severity of each symptom. Summing the severities gives an overall score. An adolescent who obtains an overall score on the CVS-Q teen© ≥ 6 points will have CVS.

Conversion of CVS-Q teen© raw scores to more accurate Rasch scores in logits (Supplementary Table S2 online) may be useful for researchers conducting clinical studies in which, for example, small variations in CVS are detected, and which require a higher precision of the instrument37.

Discussion

The CVS-Q teen© is the first questionnaire adapted and validated to assess CVS in adolescents. It is a PROM that collects ocular and visual symptoms directly from the adolescents who experience them. It presents a good fit of items and individuals to the predictions of the model. It is unidimensional, has good reliability, diagnostic capacity and test–retest repeatability.

When comparing both questionnaires (CVS-Q© vs. CVS-Q teen©), it is observed that the total number of items in the adolescent questionnaire is lower (16 vs. 14), the cut-off point being the same, although this differs for other linguistic versions that are also derived from the original29. It is observed that in both cases the item and person fit values are adequate. The adolescent version obtains higher values for sensitivity, specificity and AUC (sensitivity = 75.0% vs. 85.2%; specificity = 70.2% vs. 76.5%; AUC = 0.826 vs. 0.879), indicating that this questionnaire has a slightly better internal performance. Both questionnaires have poor targeting. Both seem to lack mild symptoms. This indicates that the CVS-Q teen© is better at differentiating adolescents with moderate and severe symptoms, as the zone of highest accuracy is in the range between 11 and 19 points. In this case, this is a logical feature of a suitable instrument for assessing CVS, rather than a deficiency of the questionnaire, as lower severities are considered to be of little clinical relevance.

As a limitation in the interpretation of our findings, it should be taken into account that the validation fieldwork was developed after COVID-19. In this period, there may have been an increase in symptomatology and even an overestimation of exposure to digital devices by adolescents. To address this issue, initially, we considered using an application to objectively measure exposure, but we faced several drawbacks. These included ethical concerns about introducing software onto personal devices and the possibility that adolescents might disconnect the application to avoid being monitored. On the other hand, it would have been preferable to have a homogeneous distribution of adolescents across different academic years. However, the DIF analysis indicated that academic year does not influence the perception of symptomatology in this case. In terms of strengths, it should be noted that a systematic, rigorous process has been followed, based on guidelines published in scientific literature, and in addition, two of the authors of the original questionnaire participated.

CVS-Q teen©, with good psychometric properties, effectively identifies cases of CVS in a reliable, valid, and straightforward manner, facilitating appropriate approaches and making possible to assess CVS in the adolescent population. Considering the high exposure to digital device use among this population, the CVS-Q teen© (1) will help to determine the prevalence of this syndrome, (2) will increase the knowledge on how the use of digital devices can affect young people, (3) will allow comparisons between adolescents with different level of exposure to digital devices, among other.

Healthcare professionals should make suitable recommendations for prevalent cases and assist in decision-making. Additionally, the CVS-Q teen© can be used in research contexts, such as studying contact lens wearers, to compare different lens types, as previous studies conducted with adults8,44.

On the other hand, as observed in the CVS-Q©, a specific feature of the CVS-Q teen© is its increased accuracy in detecting individuals with moderate to severe symptoms, while providing limited information at the lower end of the CVS construct29. Since this questionnaire assesses visual and ocular symptomatology, identifying moderate or severe cases is considered more relevant because these cases require intervention due to their greater symptom severity. In contrast, individuals with mild symptoms may be less responsive to recommendations or treatment, making the identification of severe symptoms more pertinent to clinical practice. Therefore, this characteristic should be viewed as an intentional aspect of the clinical measure rather than a limitation of the scale.

In the future, it would be highly valuable to conduct research with the CVS-Q teen© that also examines the correlation between self-reported symptoms in adolescents and the presence of objectively assessed signs from clinical tests. It is important to note that this questionnaire is specific for the Spanish adolescent population. Further research is required to validate the CVS-Q teen© in other cultural and linguistic contexts, as was done with the original CVS-Q©32,33,45.

Supplementary Information

Supplementary Information.

Supplementary Information

The online version contains supplementary material available at 10.1038/s41598-024-70821-9.

Author contributions

MSC and ERP were responsible for the conception and design of the study, and for acquiring funding. MSB was responsible for the data collection. NCS and MSB performed the formal analysis. All authors contributed to the interpretation of the data and the drafting and revising of the manuscript, as well as reading and approving the submitted version.

Funding

This work was supported by the call “Health Research Projects”, Health Research Fund of the Institute of Health Carlos III, Ministry of Science and Innovation and European Union, through European Regional Development Fund (ERDF) “A way to make Europe” [PI20/01629].

Data availability

The datasets that support the findings of the current study are available from the corresponding author MSB on reasonable request.

Competing interests

The authors declare no competing interests.

Publisher's note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Theseauthors are joint lead authors: Natalia Canto-Sancho and Mar Seguí-Crespo.
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