Introduction
We are in the era of science and technology.[1] A rapid upsurge of digitalization has influenced every aspect of human life. Digital technology has become sole enabling tool for people to interact, communicate and continue their responsibilities.[2]Increased uses of digital devices (DD) resulted in several ocular and visual symptoms conjointly known as digital eye strain (DES) or computer vision syndrome (CVS).[3,4] DES is a growing occupational and public health problem and one of the most frequent reasons for seeking medical care.[5]It is estimated that around 60 million people suffer from DES globally and that a million new cases of DES occur annually.[3]
COVID 19 pandemic has divided the world into pre-covid19 era and post covid19 era. Lockdown and social distancing leads to massive increase in digitalization and predisposed million of the individuals around the globe to increased risk of DES.[2] There was a rise in usage of internet services from 40% to 100%, compared to pre-lockdown levels.[4] As pandemic escalated quickly an epidemic was emerging in the form of DES.[2] It has influenced all aspect of life, education sector was also not spared. The educational institutions around the globe have started using different virtual educational platforms as working from home became the new norm of life.[2] Under such unanticipated circumstances DES has emerged as public health issue and its deleterious consequences may continue even when pandemic is over.[2]
As the world is vaccinating and life is coming back to pre-COVID19 norms, the adaptation to digital devises continues. The increased use of digital screens not only increases the odds of developing DES, but also occupational overuse syndrome (OOS) as well as psychosocial stress.[3] The prevalence of DES ranges from 64% to 90% and in India its reported to be 75% to 90% of computer workers.[6] Medical staff a front-line warriors and medical students an important future force, were at high risk of being infected and were continuously exposed to the stresses of providing clinical care under resource-limited condition as well as continue virtual classes and updates.[6,7] Their physical and mental state also deserves attention.[7] Many studies conducted for DES among general population but very few of them targeted to medical staff and medical student.[2,6,8,9] In the background of this current scenario, it is a matter of concern to find out the status of DES among medical student and medical staff. This survey was conducted to determine the status of DES and its determinants among medical college staff and medical students.
Materials and Methods
A cross-sectional questionnaire-based study was conducted from 16 August to 31 August 2022. The study population was medical college staff and medical students of our medical college and hospital. The Inclusion criterion was all staff of medical college and medical students who were willing to participate. Those with congenital eye disease, history of previous eye trauma, ocular diseases other than nearsightedness, farsightedness, and astigmatism were excluded. Inform consent was taken. The data collection was in accordance with the Declaration of Helsinki.
For calculating the sample size of the survey for hospital population of around 2000. we assumed that the prevalence of DES would be 77.5%.[8] To achieve 95% confidence interval (CI), 5% error margin and 1% design effect, 237 individuals were required. To compensate for loss of data, we increased the sample by 10%, so the calculated minimum sample size was261. OpenEpi, Version 3, open source calculator was used.[10]
The questionnaire was designed for this study from validated research instrument Computer Vision Syndrome Questionnaire (CVS-Q) and Digital Eye Strain and Risk Level Questionnaire (DESRIL-27).[3,9,11]It comprised of questions on demographics, frequency and pattern of computer usage, ergonomic practice, musculoskeletal disorders and awareness. (appendix: 1) Total 32 questions were prepared by mixing both questionnaires. 30 among them were closed ended. Two were likert scale (one was three point and other was four point likert scale. Those who claimed to have experienced at least one symptom of DES were considered to be having DES. Their severity were graded as Mild (symptom persist few minutes to hour), Moderate (few hours and subside after rest or sleep) and severe (need medication). Symptom Severity Scale (SSS) score was calculated, based on four components No, mild, moderate and severe, and are given Scores 0, 1, 2, and 3 respectively.[11] Therefore, the SSS score ranges from 0 to 24 for the 8 item-scale (symptoms). Total score of zero denotes absent of DES. Total SSS score were graded as Mild, moderate and severe ranged 1–8, 9–16 and 17–24 respectively. Higher total score reflects higher DES severity. Questionnaire was prepared using online Google forms and shared to hospital student and staff through whatsapp. All have equal opportunity to participate. Participants were given brief description about the purpose of study, its objectives and brief instructions to fill the questionnaire. They were requested to proceed only if they agreed to participate in the survey and were allowed to withdraw themselves at any stage if they were not willing to proceed. No incentives or rewards were offered to the participants, and their confidentiality was ensured.
Statistical Package for the Social Sciences SPSS (version 21.0) (IBM Corp., Armonk, NY USA) statistical software was used for data analysis. Descriptive data were presented as frequencies and percentages. Pearson’s chi-square test (x2) and odds ratios (ORs) were used to test and measure the association between categorical study and outcome variables. Regression analysis was conducted among the different variables to outcome. For statistical significance and precision, we used a p-value of<0.05 and a 95% confidence interval (CI).
Result
Out of 455 enrolled, 452 completed the survey (response rate 99.3%). Among them 304 (67.3%) were medical students, 77(17%) Interns and 71(15.7%) were medical staff. Females were 244(54%). Age of the participants ranged between 17 to 80 years, 342 (75.7%) were aged between 21 to 30 years. Out of total 452 participants, 340 claimed that they had experienced at least one symptom of DES. Overall prevalence was found to be 75.2% (CI0.710: 0.790).
Demographic details were shown in Table 1. 39% of them got their eyes examined every six month. Preferred place was Ophthalmologist at private hospital 72% than Govt hospital 13%. Most common eye condition among them was refractive error 51.7% than Dry eye 14.7% while most common systemic condition was thyroid 4.9% than diabetes 3.3%. DES was more common among ≥ 40 yr of age (97.3%) than younger (73.3%) (P value< 0.0023, OR=0.08, CI 0.010: 0.561, X2= 147.74).Female (82.8%) more effected than male (66.4%) (P value< 0.0001, OR= 0.40, CI 0.264: 0.636, X2= 15.41). Association of DES with refractive error (P value< 0.0016) and dry eye (P value< 0.0024) was very statistically significant.
;)
Table 1:: Demographics and behavior of Study Population
Out of 452 participants, most common complaint was headache 50.9% followed by musculoskeletal pain 47.1%. The ocular complaints in this study was experienced as blurred vision 37.1%, watering of eye 30.3%, difficulty in refocusing 27.9%, burning of eyes 26.1%, redness of eyes 21.7% and double vision 7.7%. [Table 2] DES SSS score was mild for 286 (86.7%) participants [Mean=4.3(SE ±0.1), Median = 3,Min score=1, Max score=22]. [Figure 1] Regression analysis for SSS score with risk factors reported Dry eye > age > hour of screen use > refractive error > Female gender.
Table 2:: Symptoms related to Digital eye strain
Figure 1:: Symptom severity scale score
Association between risk factor and DES is shown in Table 3. 35.6% subjects used the gadget for >5 hours daily. DES was found to be extremely statistically significant among participant using screen 5 hour or more daily (P value< 0.0005). Among them 5.1% used >5 hours daily in dark room. Association of DES with screen use in dark room was not statistically significant (P value=0.881).91.4% subjects were taking breaks while using digital screen. DES was very statistically significant among those who don’t take breaks compared to those who take break (P value< 0.0016). 48% of them prefer to use in night time. Association of DES among day or night user of screen was not statistically significant (P value = 0.96). Among all only 24.1% subjects were using lubricating eye drops, while 2.9% of them used on regular basis. DES was extremely statistically significant among non user of lubricant compared to user while using screen (P value< 0.0001).
Table 3:: Association between risk factors and Digital eye strain
Regression analysis reported DES to be effected by Female > Age > Hour of screen use > Dry eye > Refractive error. [Table 4]. Positive and significant Correlation of symptoms of DES with increase of age, hour of screen use, dry eye and refractive error was noted. ANOVA shows statistically significant regression.
Table 4:: Regression analysis of DES symptom and risk factors
Discussion
DES was prevalent in three fourth of our study population Above 40 year age group were more affected than below 40 and female more affected than male. Headache and musculoskeletal complaints were more common than ocular symptom. Association of DES with screen user >5hour per day and those who don’t take breaks while using screen were extremely statistically significant. Association of DES among day or night user of screen was not statistically significant. Association of DES with refractive error and dry eye was very statistically significant. DES was statistically significant among non-user of lubricant. Regression analysis reported DES to be effected by Female > Age > Hour of screen use > Dry eye > Refractive error.
DES was prevalent in three fourth of our study population. Our finding is consistent with an earlier study among medical students reported by Patil et.al., Iqbal et al. and Cacodcar et al.[8,12,13]while Chawla et al. and Parajuli et al. reported much higher than our study.[14,15] Rise in pattern of DES have been reported in post-Covid era, similar things are expected in medical student as well as medical staff as all prefer paperless work on digital screen.[4] In our study, though the participants are from medical college and had some understanding of digital strain and factors that can be modified to alleviate that but practical approach need to be strengthen. Taking care while using digital screen not resolve DES issue but also increases the comfort and work efficacy.
Association of DES among 40 year or above in our study was statistically significant. Abudawood et al. also found higher symptom of DES among older participants.[16] Zenbaba et al. also reported 44 years and above were nearly 3 times more likely to develop DES than younger participants.[17]This is in accordance of tear film changes noted in old age people that leads to DES symptom.[4] All using digital screen, specially above the age of 40 should take special care to avoid dryness of eye by using lubricant eye drops to avoid DES.
Association of female gender with DES in our study was found to be statistically significant. This is in accordance with earlier studies which suggest higher incidence of digital strain amongst females.[4,14,16,18] whereas Patil et al. found higher prevalence among male.[8] higher prevalence among female is attributed to higher prevalence of dry eye reported among them due to significant evaporation rate of tear film in females, cosmetics use, thus higher risk of DES.[16,18] Judicious use of lubricating and cosmetics are recommended to prevent complication in both gender.
Most common complaints reported in our study were headache and musculoskeletal pain. Symptoms experienced in DES are caused by three potential mechanisms: (i) Extraocular mechanism, (ii) accommodative mechanism, (iii) ocular surface mechanism.[4] Extraocular symptoms were higher in our study than accommodative or ocular surface related. Similar finding also reported by Sharma et al., Tawil et al. and Jahan et al.[6,19,20]In contrast Kumar et al. reported predominantly ocular symptoms.[21] In our study the most common accommodative symptoms of DES in order of severity were blurred vision >difficulty in refocusing > double vision respectively. The most common ocular surface symptoms in order of severity were watering of eye > burning of eyes >redness of eyes. Diagnosis of CVS includes detailed history taking and complete ocular examination. A comprehensive ophthalmic examinations and investigations were more accurate than subjective questionnaires regarding the diagnosis of the actual prevalence, severity and CVS-related sequelae.[12] SSS score for DES reports nine out of ten people having mild score for DES. Maximum score was reported to be 22. Regression analysis among SSS with risk factors reported, dry eye, age and hour of screen use having greater effect on DES than refractive error and Female gender. Although each of these risk factor has statistically significant association with SSS score of DES. We recommend digital screen user having any of these factors should take extra precaution to avoid worsening of DES, especially if they are suffering from dry eye, elderly and > five hour use of screen work. 20-20-20 rule (taking a 20-s break every 20 min to look at an object 20 feet away) is effective measure to avoid DES.[13,14] Ergonomic use and awareness practices also need to be implemented [Table 5].[14]
Table 5:: Prevalence of DES among medical student and Medical staff from different parts of the world
Association of >5 hour per day digital screen usage and symptoms of DES in our study was statistically significant. Similar finding was reported by other study also.[3,12,19,22] Prolonged and continuous screen-hours require the bilateral use of both sets of intraocular and extraocular muscles (e.g., ciliary, constrictive pupillae, and medial recti muscles) to adjust the focus and achieve the best visual performance, which finally increase DES severity.[12] Association of DES among those who don’t take breaks while using screen was found to be statistically significant in our study. Similar finding was reported by Cacodcaret al.[13] While Tawil et al. found it to be non significant.[19]Students who took frequent breaks were at a lower risk of developing symptoms of DES as compared to those who did not take breaks.[13] Taking regular small breaks may relax the accommodation process of the eyes, thereby preventing eye strain.[13]
Association of DES with screen user during day time compared to night was not found to be statistically significant in our study. This is in contrast to Iqbal et al. who reported DES more in night users.[12] Tawil et al. reported using devices in a dark room was not statistically significant but positively associated with DES symptoms.[19] Though our study similarly reported no statistical significance but its positive association cannot be ruled out. As exposure to mobile phone emissions at night time could have an effect on melatonin onset time. Electromagnetic field produced due to electrical appliances may play a significant role in influencing the circadian system, amount and quality of sleep, increased fatigue that eventually leads to DES.[8] Further study is needed including other factors like room light illumination level while using digital screen in night.
Association of DES with refractive error in our study was found to be statistically significant. Similar association was reported by Iqbal et al.[12] In contrast refractive errors showed no significant association with DES by Abudawood et al. and Almousa et al.[16,18] Nearly half of our study population have refractive error. About 84% of them were using glass correction that is quite high as reported by Abudawood et al.(40.9%)and Jahan et al.(60%).[16,20] Contact lens wear is 2.4% that is less than reported in Abudawood et al. (10.4%) and Jahan et al.(22.5%).[16,20] About 12% uses both glasses and contact lens. High uses of glasses and lower use of contact lens in our study is a positive sign toward decreasing DES as uncorrected refractive errors lead to squinting and poor visualization contributes to eye strain where as contact lenses disrupts the normal surface tear film and causes discomfort as well as increase DES symptoms.[3] Wearing glasses instead of contact lenses is recommended to reduce symptoms of DES.[23]
Association of DES with dry eye was found to be statistically significant in our study. Similar result was reported by other study also.[4,16] 14.6% participants were known to have dry eye disease in our study and only 2.9% of them were using lubricant on regular basis. Cacodcar et al. also reported 13.63% dry eye whereas Tawil et al. found only 5.6%.[13,19] This is explained by the reduced blinking reflex while seated in front of the screen for a long time, which contributes to improper tear production and increase evaporation, thus exaggerating dry eye disease that leads to DES.[16]Our study reported DES extremely statistically significant among non-user of lubricant. Zalat et al. also reported use of lubricant were significantly associated with negative CVS.[24] Moist ocular surface has soothing effect on each blink that decreases ocular discomfort while using digital devises.
Regression analysis reported DES symptoms to be effected by female > age > hour of screen use > dry eye > refractive error. Positive and significant Correlation of symptoms of DES with increase of age, hour of screen use, dry eye and refractive error was noted. When we analyze presence or absence of DES symptoms with the female gender, it was found to be maximally associated but when we analyze the total SSS score of DES with the female gender, it was found to be minimally associated. Although in both regression analysis if was statistically significant. We have no explanation for this and further study is recommended.
This study has some limitations also. It was a cross-sectional study that just presented a snapshot regarding DES at one point in time without giving much idea about the causative factors. The results are based only on subjective perception of symptoms and no objective evaluation was done. This study is based on one center participants so its effect on general population should be deal with caution. Even then, the results of our study can provide baseline data to stakeholders to devise effective strategies to reduce its rapid upsurge during pandemic.
Recommendation
Awareness campaign should be circulated on various platforms to improve quality of life. Pragyata guidelines for digital education by HRD Ministry of India should be followed by institution as well as students.[25] Breaks should be implemented according to the 20/20/20 rule. Use of ergonomic practices should be encouraged. Voluntary forceful blinking during screen time should be encouraged, which squeezes the Meibomian glands to secrete the lipid layer of the tear film. Applicants with an underlying ocular issue, such as chronic dry eye disease and uncorrected refractive error, should have an eye examination to prevent unintentionally exacerbating the condition. A preservative-free artificial tear preparation can also be recommended. Low-certainty evidence suggested that oral omega-3 supplementation reduces dry eye symptoms in symptomatic computer user.[26]
Conclusion
Three fourth of participants suffer from DES and majority of them having mild grade of symptoms. DES is highly prevalent among medical students and medical staff. Health issues related to excessive use of digital devices is alarmingly high especially in post-Covid era due to digitalization of education and work to promote paperless or Go-Green. There is dire necessity to address this burning public health issue. The most significant preventive measure is applying the 20-20-20 rule with ergonomics.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
1. Rathore I. Computer Vision Syndrome–An Emerging Occupational Hazard. Research Journal of Science and Technology 2017;9:293-7
2. Noreen K, Ali K, Aftab K, Umar M. Computer Vision Syndrome (CVS) and its Associated Risk Factors among Undergraduate Medical Students in Midst of COVID-19. Pakistan Journal of Ophthalmology 2021;37
3. Gammoh Y. Digital eye strain and its risk factors among a university student population in Jordan: A cross-sectional study. Cureus 2021;13:e13575
4. Kaur K, Gurnani B, Nayak S, Deori N, Kaur S, Jethani J, et al. Digital eye strain-A comprehensive review. Ophthalmology and Therapy 2022;1-26
5. Zayed HAM, Saied SM, Younis EA, Atlam SA. Digital eye strain: Prevalence and associated factors among information technology professionals, egypt. Environ Sci Pollut Res Int 2021;28:25187-95
6. Sharma S, Ratha SK. Computer vision syndrome and its risk factors among medical students of a tertiary care centre in Odisha: A cross-sectional study. International Journal of Health Systems and Implementation Research 2021;5:42-9
7. Li Z, Yi X, Zhong M, Li Z, Xiang W, Wu S, et al. Psychological distress, social support, coping style, and perceived stress among medical staff and medical students in the early stages of the Covid-19 epidemic in china. Front Psychiatry 2021;12:664808
8. Patil A, Bhavya, Chaudhury S, Srivastava S. Eyeing computer vision syndrome: Awareness, knowledge, and its impact on sleep quality among medical students. Ind Psychiatry J 2019;28:68-74
9. Iqbal M, El-Massry A, Elagouz M, Elzembely H. Computer vision syndrome survey among the medical students in Sohag University Hospital, Egypt. Ophthalmology Research: An International Journal 2018;8:1-8
10. Open Source Epidemiologic Statistics for Public Health. Version 3.01.Available from https://www.openepi.com/SampleSize/SSPropor.htm [Last accessed on 08 Nov 22]
11. Hamid Z, Rahman HA, Idris FI, Naing L. The Development and Validation of a Questionnaire Measuring Digital Eye Strain and Risk Level (DESRIL-27).20221-19https://doi.org/10.21203/rs.3.rs-1342108/v2.
12. Iqbal M, Said O, Ibrahim O, Soliman A. Visual sequelae of computer vision syndrome: A cross-sectional case-control study. J Ophthalmol 2021;2021:6630286
13. Cacodcar JA, Raiturcar TP, Fernandes RR, Dessai SR, Kantak VS, Naik R. Knowledge, attitudes and practices of computer vision syndrome among medical students in Goa. Epidemiology International (E-ISSN: 2455–7048) 2021;6:9-14
14. Chawla U, Yadav P, Chugh JP, Chadha G. Study of Digital Eye Strain due to Extended Digital Device Use among Undergraduate Medical Students during the COVID-19 Pandemic: A Cross Sectional Study. International Journal of All Research Education and Scientific Methods 2021;9:991-8
15. Parajuli BR, Koirala S, Bajracarya A. Computer vision syndrome: A rising problem during COVID-19 period amongst students and online workers. Journal of Patan Academy of Health Sciences 2021;8:6-9
16. Abudawood GA, Ashi HM, Almarzouki NK. Computer vision syndrome among undergraduate medical students in King Abdulaziz University, Jeddah, Saudi Arabia. Journal of Ophthalmology 2020;20:1-7
17. Zenbaba D, Sahiledengle B, Bonsa M, Tekalegn Y, Azanaw J, Kumar Chattu V. Prevalence of computer vision syndrome and associated factors among instructors in Ethiopian Universities: A web-based cross-sectional study. The Scientific World Journal 2021;21:1-8
18. Almousa A, Aldofyan M, Kokandi B, Alsubki H, Alqahtani R, Gikandi P, et al. Prevalence of Computer Vision Syndrome and Patterns of Electronic Devices Usage before and during COVID-19 Pandemic among Medical Students in Riyadh, Saudi Arabia. 2022;1-19https://doi.org/10.21203/rs.3.rs-1103049/v1.
19. Al Tawil L, Aldokhayel S, Zeitouni L, Qadoumi T, Hussein S, Ahamed SS. Prevalence of self-reported computer vision syndrome symptoms and its associated factors among university students. Eur J Ophthalmol 2020;30:189-95
20. Jahan F, ul Islam Z, Rafei M. Factors Leading Computer Vision Syndrome in Medical Students: A Descriptive Analysis. International Journal of Public Health Research 2018;6:78-82
21. Kumar BS. A study to evaluate the knowledge regarding computer vision syndrome among medical students. Biomed Pharmacol J 2020;13:469-73
22. Al-Swailem S, Almalki AM, Alblowi M, Aldosari A, Khandekar R. Population perceived eye strain due to digital devices usage during COVID-19 pandemic. Investigative Ophthalmology & Visual Science 2022;63:3371-A0158
23. Dahshan D, Rosdahl JA. Digital eye strain during the virtual interviews: Evidence-based strategies for medical students. Digit J Ophthalmol 2022;28:22-5
24. Zalat MM, Amer SM, Wassif GA, El Tarhouny SA, Mansour TM. Computer vision syndrome, visual ergonomics and amelioration among staff members in a saudi medical college. Int J Occup Saf Ergon 2022;28:1033-41
25. PragyataGuidelines for Digital Education, Ministry of HRD Government of India. Available from https://www.education. gov.in/sites/upload_files/mhrd/files/pragyata-guidelines_0.pdf [Last accessed on 05 Oct 22]
26. Singh S, McGuinness MB, Anderson AJ, Downie LE. Interventions for the management of computer vision syndrome: A systematic review and meta-analysis. Ophthalmology 2022;129:1192-215
