Abstract
Background
Smartphones have become essential tools in education, particularly in medical studies. However, their prolonged use has been associated with digital eye strain (DES) and various ocular health problems. The present study aimed to measure the duration and pattern of smartphone use and assess the effects of smartphone use on ocular health among medical students.
Methods
A descriptive cross-sectional study was conducted on 345 medical students (first to final year) from private medical and dental colleges using nonprobability convenience sampling. The sociodemographics, usage patterns, and ocular symptoms were evaluated using a validated questionnaire. Data were analyzed using SPSS version 26 (IBM Co.); the chi-square test was used to assess associations (p < 0.05).
Results
All study participants reported smartphone use, with 53.9% initiating between the ages of 12 and 18 years. Excessive usage was perceived by 79.4%, and 41.2% reported > 8 hours/day. Academic and recreational use was common (91.9%). Reduced blinking (< 15-20/min) was reported by 75.9%, and 40.6% never rested their eyes. The frequency of ocular symptoms was high [itching (82.0%), dryness (81.7%), redness (79.7%), photophobia (79.1%), and lacrimation (73.9%)]; eye fatigue occurred in 63.5%. A screen time of > 8 hours was significantly associated with dryness (p = 0.02), lacrimation (p = 0.04), and itching (p = 0.03). Infrequent rest was correlated with dryness (p < 0.001) and itching (p = 0.05). The symptoms occurred irrespective of refractive status.
Conclusion
Smartphone use is universal among medical students, with substantial daily screen exposure and poor digital health resulting in a high prevalence of DES. Awareness campaigns promoting the “20-20-20 rule,” regular blinking, and ergonomic practices are essential.
Keywords: Digital eye strain, Medical students, Ocular health, Screen time, Smartphone use
INTRODUCTION
Smartphones have become an essential part of our lives. It can run multiple applications, beyond the traditional use of phones for calling, taking photos, or texting, thus becoming an integral part of our community. Beyond serving as a communication device, it also acts as a social companion and technological asset that improves our personal and professional quality of life by enhancing communication, accommodating multiple tasks, enabling faster interaction with the world, providing better and easier access to information, and integrating into various aspects of daily routine [1].
Various studies worldwide have shown that smartphone use is increasing among young children and adolescents [2]. Study conducted in 2023 in Hong Kong showed that 81.3% of school children 10-14 years of age have smartphones [3]. The same was observed in the UK (91%) and the USA (95%) [4]. According to the American Optometric Association, children aged 0 to 8 years spent 48 minutes/day on smartphones, compared to schoolchildren who spent 3 hours/day on smartphones [5]. In Hong Kong, children aged 10 years and above spend 30 hours per week on smartphones, specifically on the Internet [3].
Pakistan is the fifth most populous country in the world, with more than 220 million people, and a median age of 23. The smartphone penetration has gone from 10% in 2014 to 51% by 2020, and 77% are between 21 and 30 years of age [6].
Smartphones are indispensable tools in modern education, especially in medical studies, where they are used as a powerful tool for learning and communication. Medical students use smartphones to access medical resources, the latest medical research, educational apps, and clinical tools; manage academic tasks and drug references; and learn clinical skills [7]. Although smartphones can make medical students’ lives easier, they can also have adverse effects on their physical and psychological well-being, specifically leading to ocular and neurological health problems [8].
Digital eye strain (DES) causes multiple ocular and vision-related problems, such as diplopia, blurred vision, lacrimation, itching, and redness, and can affect anyone, especially smartphone users who spend much of their time on the device, whether for studies or enjoyment. Duration and pattern of smartphone use are closely associated with the development of ocular problems [9]. A study conducted in Jordan in 2021 showed that smartphone use for more than 6 hours caused vision problems, including eye strain, excessive lacrimation, and photophobia, in 93.9% of students [10]. Various studies have concluded that time spent using smartphones is associated with refractive errors [11,12]. Another study conducted in Korea concluded that a reduced blink rate while using a smartphone is associated with dry eye disease [13].
Better knowledge and insight into the prevalence, patterns, and impact of smartphone use on ocular health among medical college students are essential for planning and implementing prevention programs. There is limited literature on the effects of smartphone use on ocular health among medical students. Therefore, this study aims to determine the frequency and pattern of use of smartphones and to assess their impact on ocular health among medical students at a private medical and dental college.
MATERIALS AND METHODS
A descriptive cross-sectional study was conducted at a private medical college. Nonprobability convenience sampling was used. Study participants included 345 registered first- to final-year the Bachelor of Medicine, Bachelor of Surgery students who provided informed consent. The relatively lower participation of first-year students was due to their limited availability during the data collection period, as they were engaged in orientation activities and adjusting to academic schedules. The study was approved by the institutional review board.
A structured, previously validated questionnaire designed by Issa et al. [14] was used as the study tool. The questionnaire consisted of the following three parts: Section I included questions on socio-demographic data. Section II included questions (1-10) on the pattern of smartphone use. Section III included questions (11-14) on the ocular problems. Data were entered and analysed using the Statistical Package for the Social Sciences version 26 (IBM Co.). Data was presented as tables and graphs. Descriptive statistics were used in terms of numbers and percentages. A chi-square test of significance was applied to examine associations between background variables and smartphone use, as well as between background variables and the presence or severity of ocular symptoms. The cut-off point for significance was p < 0.05.
RESULTS
The current study included a total of 345 MBBS students of all five years (n = 345).
1. Demographic data of students and consideration about smartphone use
Of the total 345 students, 131 (38%) were male, and 214 (62%) were female. The sex pattern in our study reflected institutional enrollment patterns, with the majority of students being female. The majority of students were from the third year of MBBS. A total of 200 (58%) are day scholars. The majority of students were between 20 and 23 years old (Table 1).
Table 1.
Demographic data of students and considerations about smartphone use
| Variables | Categories | Frequency (%) |
|---|---|---|
| Sex | Male | 131 (38.0) |
| Female | 214 (62.0) | |
| Current academic year | First | 27 (7.8) |
| Second | 69 (20.0) | |
| Third | 97 (28.0) | |
| Fourth | 66 (19.0) | |
| Final | 86 (24.9) | |
| Residential status | Day scholar | 200 (58.0) |
| Boarder | 145 (42.0) | |
| High school qualification | Faculty of Science | 287 (83.2) |
| A-Level | 50 (14.5) | |
| American Board | 8 (2.3) |
2. Pattern of smartphone use
A total of 100% (345) of students used smartphones, of whom 186 (53.9%) started using them at ages 13-18. The majority of them (53.9%) began using smartphones between the ages of 12 and 18 years, and 79.4% used smartphones more than expected. 41.2% used more than 8 hours a day. In 75.9% of students, the blinking rate was less than 15-20 times per minute (Table 2).
Table 2.
Pattern of smartphone use
| Variables | Categories | Frequency (%) |
|---|---|---|
| Smartphone use | Yes | 345 (100) |
| No | 0 (0.0) | |
| Age of start using smartphone | Less than 6 years old | 20 (5.8) |
| 6-12 years old | 104 (30.1) | |
| 12-18 years old | 186 (53.9) | |
| More than 18 years old | 35 (10.1) | |
| Using a smartphone more than expected | Yes | 274 (79.4) |
| No | 71 (20.6) | |
| Average screen time per day | Less than 2 hours | 26 (7.5) |
| 2-4 hours | 29 (8.4) | |
| 5-6 hours | 36 (10.4) | |
| 7-8 hours | 112 (32.5) | |
| More than 8 hours | 142 (41.2) | |
| Purpose of smartphone use | Study | 5 (1.4) |
| Recreational | 23 (6.7) | |
| Both | 317 (91.9) | |
| Desired brightness of the smartphone | Equal to the surrounding light | 162 (47.0) |
| More than surrounding light | 46 (13.3) | |
| Less than surrounding light | 137 (39.7) | |
| Distance of using a smartphone | Between 16-20 inches | 203 (58.8) |
| More | 25 (7.2) | |
| Less | 117 (33.9) | |
| Usage of smartphone increased in recent years | Yes | 298 (86.4) |
| No | 47 (13.6) | |
| The interval at which you rest your eyes while using a smartphone? | After every 20 minutes | 29 (8.4) |
| After more than 20 minutes | 176 (51.0) | |
| I do not give my eyes rest at all | 140 (40.6) | |
| Average blinking rate while using smartphone | 15-20 times per minute | 67 (19.4) |
| More | 16 (4.6) | |
| Less | 262 (75.9) |
3. Ocular problems and smartphone use
The medical students who experienced dry eyes were 81.7%, 73.9% experienced lacrimation, and 82.0% experienced itching with smartphone use. Other ocular problems, such as eye fatigue, were experienced by 63.5% of the medical students. The majority of students (73.3%) reported that their ocular problems increased with smartphone use. Students with no family history of ocular problems were 57.1% (Table 3).
Table 3.
Ocular problems and smartphone use
| Variables | Categories | Frequency (%) |
|---|---|---|
| Dryness | Yes | 282 (81.7) |
| No | 63 (18.3) | |
| Lacrimation | Yes | 255 (73.9) |
| No | 90 (26.1) | |
| Itching | Yes | 283 (82.0) |
| No | 62 (18.0) | |
| Redness | Yes | 275 (79.7) |
| No | 70 (20.3) | |
| Blurred vision | Yes | 269 (78.0) |
| No | 76 (22.0) | |
| Photophobia | Yes | 273 (79.1) |
| No | 72 (20.9) | |
| Other ocular problems | Eye pain | 1 (0.3) |
| Eye fatigue | 219 (63.5) | |
| No other problem | 125 (36.2) | |
| What are the vision problems you suffer from? | Myopia | 130 (37.7) |
| Hypermetropia | 26 (7.5) | |
| Astigmatism | 18 (5.2) | |
| None | 171 (49.6) | |
| Increase in ocular problems with the use of smartphones | Yes | 253 (73.3) |
| No | 92 (26.7) | |
| Family history of ocular problems | Yes | 148 (42.9) |
| No | 197 (57.1) |
4. Ocular problems and pattern of smartphone use
Table 4 illustrates the association between ocular problems and smartphone use patterns. A total of 122 students with an average screen time of more than 8 hours experienced dry eyes (p = 0.02), 114 students with the same average screen time experienced lacrimation (p = 0.04), and 112 students with more than 8 hours of average screen time felt itching in the eyes after using the smartphone (p = 0.03). A total of 144 with dryness (p < 0.001), 122 with itching (p = 0.05), and 120 with blurred vision (p = 0.08) rest their eyes after more than 20 minutes of smartphone use (Table 4).
Table 4.
Ocular problems and pattern of smartphone use
| Variables | Categories | Ocular problems (n = 345) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dryness | Lacrimation | Itching | Blurred vision | |||||||||||||
| Yes | No | x2 | Yes | No | x2 | Yes | No | x2 | Yes | No | x2 | |||||
| Using a smartphone more than expected | Yes | 227 | 55 | 0.29 | 206 | 68 | 0.3 | 227 | 56 | 0.43 | 218 | 51 | 0.16 | |||
| No | 47 | 16 | 49 | 22 | 47 | 15 | 56 | 20 | ||||||||
| Average screen time per day (hr) | < 2 | 23 | 3 | 0.02 | 19 | 7 | 0.04 | 28 | 11 | 0.03 | 16 | 10 | 0.18 | |||
| 2-4 | 23 | 6 | 20 | 9 | 31 | 33 | 21 | 8 | ||||||||
| 5-6 | 33 | 3 | 20 | 16 | 26 | 11 | 31 | 5 | ||||||||
| 7-8 | 81 | 31 | 82 | 30 | 86 | 3 | 89 | 23 | ||||||||
| > 8 | 122 | 20 | 114 | 28 | 112 | 4 | 112 | 30 | ||||||||
| Distance of using a smartphone | Between 16-20” | 170 | 33 | 0.39 | 154 | 49 | 0.23 | 169 | 34 | 0.64 | 159 | 44 | 0.36 | |||
| More | 21 | 4 | 15 | 10 | 19 | 6 | 22 | 3 | ||||||||
| Less | 91 | 26 | 86 | 31 | 95 | 22 | 88 | 29 | ||||||||
| The interval at which you rest your eyes while using smartphone? | After every 20 minutes | 29 | 52 | 0.00 | 63 | 18 | 0.34 | 64 | 26 | 0.05 | 56 | 25 | 0.08 | |||
| After > 20 minutes | 140 | 10 | 105 | 45 | 122 | 32 | 120 | 30 | ||||||||
| I don’t give my eyes rest | 113 | 1 | 87 | 27 | 97 | 4 | 93 | 21 | ||||||||
| Average blinking rate while using smartphone | 15-20 times/min | 59 | 14 | 0.00 | 55 | 18 | 0.54 | 60 | 28 | 0.02 | 62 | 11 | 0.07 | |||
| More | 14 | 39 | 42 | 11 | 46 | 30 | 36 | 17 | ||||||||
| Less | 209 | 10 | 158 | 61 | 177 | 4 | 171 | 48 | ||||||||
Fig. 1A showed no statistically significant association between increased ocular problems and the feeling of using a smartphone more than expected (p < 0.001). There is a statistically significant association between an increase in ocular problems and average screen time per day (p = 0.12) as depicted in Fig. 1B. Fig. 1C showed a statistically significant association between an increase in ocular problems and age of smartphone use (p < 0.001).
Fig. 1.
Association between an increase in ocular problems and smartphone use. (A) Association between average screen time/day and increase in ocular problems. (B) Association between more than expected smartphone use and increase in ocular problems. (C) Association between age of start using smartphone and increase in ocular problems. *p < 0.001.
DISCUSSION
The study investigated patterns of smartphone use and their impact on ocular health among medical students. The results showed that all 345 respondents (100%) reported using smartphones, with the majority (53.9%) having started using smartphones between the ages of 12 and 18 years, and 317 (91.9%) respondents stated their primary purpose for smartphones was both study and recreational use. These results were fairly consistent with a study conducted in Iraq, which reported that 90.8% of the general university students used smartphones regularly, with most beginning their use between the ages of 12 and 18 years [11]. Of the 345 study participants, 142 (41.2%) reported using their smartphones for more than 8 hours a day, and another 112 (32.5%) reported using them for 7-8 hours a day. These results are substantially higher than those reported by Elsheikh et al. [15] where the most common daily usage was between 4-6 hours (30.2%) whereas another study conducted by Chidi-Egboka et al. [16] among school-aged children and adolescents in Hong Kong noted that 50.8% of the study participants used their smartphones for more than 4 hours a day.
In this study, ocular symptoms were widely reported, with itching (82.0%), dryness (81.7%), and redness (79.7%) being the most common. These symptoms were notably higher than those reported in previous global studies among general university students and school-aged children [17,18]. One possible explanation for this disparity may be due to the intense academic demands placed on medical students which results in longer and more frequent screen exposure which in turn leads to a higher burden of ocular symptoms, a phenomenon also observed in this study in which a statistically significant association between increased screen time and the occurrence of ocular symptoms such as itching, dryness and lacrimation. Furthermore, the study by Sharma et al. [19] and Wang et al. [20] supports these associations in which they observed that students with ≥241 min/day of smartphone use had the highest baseline scores of DES while also noting a significant increase in DES scores at a 1-year follow up among students with 181-240 min/day of smartphone use.
One of the most striking findings was that 274 (79.4%) students felt that they were using their phones more than they should, and 298 (86.4%) stated that their phone usage had increased over the past years, a finding consistent with previously conducted global studies [21,22]. Despite this, only 8.4% of participants followed basic eye care practices, such as the “20-20-20 rule” for resting eyes, and 75.9% reported lower-than-normal blinking rates while using their smartphones, both of which are known contributors to DES. These findings support the literature of Datta et al. [23] that links poor digital hygiene, such as inadequate blinking and prolonged uninterrupted screen time, to symptoms of DES. Interestingly, despite the high prevalence of DES symptoms, 49.6% of the study population reported having no refractive error. This suggests that symptoms of DES can occur in individuals without underlying vision problems and highlights the importance of distinguishing between symptoms of functional eye strain and those of structural refractive errors. Especially since a study conducted in Pakistan found that patients with pre-existing refractive errors reported more symptoms of DES, with 78.1% of spectacle users and 96.4% of contact lens users reporting symptoms suggestive of DES [24]. Moreover, significantly severe DES symptoms have been reported in several studies in patients with uncorrected refractive errors [25,26]. The study findings demonstrated that increased smartphone use leads to ocular consequences, including worsening eye problems. Therefore, the application and awareness of preventive strategies at the institutional and government levels may help reduce the severity of symptoms and thus improve the prognosis. These strategies are: encouraging practice of the 20-20-20 rule, which is that every 20 minutes, look 20 feet away for 20 seconds, encouraging regular blinking and screen breaks; adjusting screen brightness; awareness and education seminars about digital eye hygiene.
1. Conclusion
Smartphone use is universal among medical students, with substantial daily screen exposure and inadequate digital hygiene practices. The prevalence of DES symptoms is alarmingly high, particularly among those with prolonged screen time and infrequent eye rest. These findings highlight an urgent need for awareness campaigns and preventive strategies such as adherence to the “20-20-20 rule,” regular blinking, time management training, and optimal screen ergonomics.
2. Limitations
The study relies on self-reported data, which may be subject to recall bias or over- or under-reporting, particularly regarding symptom severity and screen time estimates. Secondly, the lack of objective clinical ophthalmologic evaluations (e.g., the Schirmer test for dry eyes, slit lamp examinations) limits the ability to confirm the questionnaire-reported symptoms. Furthermore, due to financial constraints, the study population included students from only a single medical institution, which, coupled with the relatively small sample size, may limit the generalizability of the results. Lastly, confounding factors such as the use of spectacles, corrective contact lenses, and blue light filters were not controlled for, which may affect the frequency and severity of reported symptoms.
Acknowledgements
None.
Funding Statement
• Funding: None.
NOTES
• Authors’ contributions: S.N. participated in conceptualization and in supervision of the study. S.M.I.R. participated in data curation and data analysis. M.M. and I.N.A.M. participated in writing – original draft. M.K., M.A., and M.U. participated in writing – review & editing.
• Conflicts of Interest: No conflict of interest.
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