Abstract
PURPOSE:
Refractive errors (REs) are common and continue to increase globally, particularly myopia. Uncorrected REs are the second leading cause of preventable blindness and the most common cause of visual impairment. The main objective of this study is to assess the prevalence of REs and to investigate its associated risk factors among medical students of the Jazan region, Saudi Arabia.
METHODS:
An observational analytical cross-sectional study was conducted among a random sample of 447 medical students at Jazan University. Eye examination was conducted using an autorefractor test (Huvitz HRK-8000A Autorefractor Keratometer) to measure spherical refraction (emmetropia, myopia, and hyperopia) and cylindrical refraction (astigmatism). Factors associated with myopia and hyperopia were evaluated using logistic regression models.
RESULTS:
The overall prevalence of REs was 48.8% (95% confidence interval [CI] [44.2, 53.4]). The prevalence of REs among female medical students was 55.1% (95% CI [48.6, 61.5]), which was significantly higher than that among males (42.3%, 95% CI [36.0, 48.9]), with a P = 0.007. Of the 447 medical students examined, approximately one-third (33.8%) had myopia, 10.5% had astigmatism, and only 10.5% had hyperopia. The results of logistic regression indicated that females were 52% more myopic than males (odds ratios [OR] = 1.52, 95% CI [1.04, 2.22]), while participants with both parents having a history of REs were twofold more myopic than students with no family history of REs (OR = 2.01, 95% CI [1.2, 3.4]). A history of blurred vision also increases the risk of myopia by seven times (OR = 7.2, 95% CI [6.4, 11.3]).
CONCLUSION:
RE among medical students is a problem. Thus, it needs to be assessed carefully before students choose a specialty that may need very good near and far vision for postgraduate study.
Keywords: Hyperopia, Jazan, medical student, myopia, refractive error, spherical refraction
Introduction
Refractive errors (REs) are defined as a condition, in which the optics of the nonaccommodating eye are unable to take parallel light rays to concentrate on the retina. REs can present singularly such as myopia (nearsightedness), hyperopia (farsightedness), and astigmatism, or combined, such as myopic astigmatism and hyperopic astigmatism.[1] A recent meta-analysis study involved data from 98 countries revealed that uncorrected RE was among the leading causes for moderate or severe vision impairment.[2] The WHO estimated that severe REs accounted for 5 million blind persons globally.
For prevention of the blindness, the WHO and the International Agency for the Prevention of Blindness identified uncorrected REs as one of the priorities program, through Vision 2020 initiative to eliminate avoidable blindness.[3] Uncorrected REs burden individuals and society with increased morbidity, economic hardship, and decreased opportunities for education and productivity.[4]
REs are now prevalent and continue to increase globally, particularly myopia.[5] The risk of myopic complications, such as cataracts, glaucoma, retinal detachment, and blindness, is increasing as well.[6] Several studies have shown that the major factors associated with myopia were genetic and environmental factors, as they contribute to raising myopia around the world.[7] The literature suggested that watching TV, especially from a short distance, using electronic devices for a long time, using dim light while reading, family history, gender (female), and near work activity are major risk factors for REs.[8,9,10]
Worldwide, numerous studies were conducted on RE and provided highly variable results. In Norway, 47% of students were myopic.[11] In Malaysia, it is stated that 7% of medical students were hyperopic,[12] while the prevalence of myopia was 89.8% in Singapore.[13]
In KSA, relatively few studies have been conducted among medical students. Studies that had been conducted in Qassim, Aljouf, and Riyadh showed relatively high myopic prevalence among the students.[5,8,9] Among Qassim and Riyadh students, studies showed that approximately 50% of them were myopic.[5,9] Aljouf University study showed the highest rates of REs at 83.1% prevalence of myopia.[8] In contrast, hyperopia and astigmatisms had a lower rate than myopia, with a prevalence between 3% and 32% in Qassim and Aljouf studies, respectively.[5,8] In Jazan region, several studies on REs were conducted, but no research has been conducted among medical students. This study aims to assess the prevalence of REs and its associated risk factors among medical students of Jazan University.
Methods
Study design, setting, and population
An analytical, cross-sectional study was conducted among medical students of Jazan University. Jazan University is a leading higher educational institution in the region, with 26 faculties enrolling more than 50,000 students. The estimated number of medical students was 475 in the male section and 509 in the female section. Inclusion criteria were being a medical student (males and females) who registered for the academic year 2019/2020 and having signed the consent form to participate in the study. The exclusion criteria involved any prior history of ocular diseases or procedures.
Sampling procedures
The sample size for this study is calculated to be 460 students. The estimation was based on the sample size formula for cross-sectional study designs, using the following parameters: prevalence of RE = 50% (as no previous study on RE was conducted at Jazan University), a 95% confidence interval (CI), and an error of not more than 5%. Furthermore, the study assumed a nonresponse rate of 15%. The final sample size was equally divided into males and females as there is equal proportion of males and females. The sample size was then stratified according to the different classes within the Faculty of Medicine at Jazan University.
Data collection techniques and study instrument
A self-administered questionnaire and a clinical checklist involving the results of the eye test were used for data collection. The checklist involved the collection of clinical data using an ophthalmology mobile clinic. The self-administered questionnaire involves four sets of data. The first part includes demographic information (age, gender, place of residence, etc.). The second part includes data regarding knowledge about having a RE and family history, whereas the third part includes data regarding lifestyle (suffering from blurred vision, feeling a headache, a previous eye operation, and usage of contact lenses). The fourth part includes risk factors involving the average number of hours/days spent on near work (reading, usage of a mobile, usage of an iPad or computer, playing a video game, and watching TV).
Eye examinations
After completing the questionnaire, all participants went to the examination. The examination was conducted by an optometrist and involved one step, which was the measurement of objective refraction. This was done by an autorefractor test (Huvitz HRK-8000A Autorefractor Keratometer) to measure spherical refraction (emmetropia, myopia, and hyperopia) and cylindrical refraction (astigmatism). The autorefractor examination was done by placing each student's chin on the chin holder and asking him/her to view the image with both eyes. The same examiner used the same device for all the participants.
Operational definitions
The definitions of RE were based on the following. Myopia was considered if spherical equivalent refraction (SER) ≤0.75 D, emmetropia if SER is between −0.75 D and 1 D, and hyperopia if SER ≥1 D. Myopia was further classified as low, moderate, and severe. Low myopia was defined as SER of −0.75 to −2.99 D, moderate as SER from −3.00 to −5.99 D, and severe as SER ≥−6.00 D. Astigmatism ≥1.00 was defined as diopter of cylinder.[5]
Ethics
This study was conducted in accordance with the bioethics standards of the Kingdom of Saudi Arabia. Ethical approval was obtained from the Institutional Review Board of Jazan University. The study participants were told that they had the right not to participate in the study. Moreover, the participants' privacy was respected, and the data were kept confidential and were utilized for study purposes only.
Data analysis
The data were entered and analyzed using SPSS version 20 (SPSS Inc., Chicago, IL, USA). Data analysis involved descriptive statistics analysis and some techniques of inferential statistics. The descriptive statistics included simple tabulation, frequencies, and cross-tabulations. The Chi-squared test was used to test differences in proportion. Univariate logistic regression models were used to assess factors associated with myopia/hyperopia. The models' results are reported as odds ratios (OR) with 95% CI. A P < 0.05 was used as the cutoff level to indicate statistical significance.
Results
A total of 447 medical students signed the study consent and participated in the eye examinations (222 males and 225 females), with a nonresponse rate of 2.8% (447 out of 460). The sociodemographic characteristics of the students are described in Table 1. Of the sample, 56.4% were in the age group of 21–23 years. The mean age was 21.7 years for both males and females. Almost 49.0% of the students in the sample had a Cumulative Grade Points Average equivalent of very good. Students with no family history of RE formed 31.8% of the sample. The same table presents the mean values of spherical equivalent RE for both eyes by different characteristics. The overall mean refraction was −0.91 ± 1.83 (95% CI [−1.08, −74]) in the right eye compared to −0.78 ± 1.67 (95% CI [−0.93, −62]) in the left eye.
Table 1.
Background characteristics and mean values spherical equivalent refraction
| Characteristic | n (%) | Mean±SD | |
|---|---|---|---|
| Right eye SER | Left eye SER | ||
| Gender | |||
| Male | 222 (49.7) | -0.88±1.80 | -0.73±1.55 |
| Female | 225 (50.3) | -0.94±1.87 | -0.83±1.78 |
| Age groups (years) | |||
| 18-21 | 120 (26.8) | -0.79±1.58 | -0.72±1.67 |
| 21-23 | 252 (56.4) | -0.99±2.00 | -0.84±1.77 |
| 24-27 | 71 (15.9) | -0.8±1.56 | -0.70±1.29 |
| Study level (years) | |||
| 2nd | 94 (21.0) | -0.97±1.69 | -0.82±1.88 |
| 3rd | 118 (26.4) | -0.88±1.80 | -0.93±1.65 |
| 4th | 108 (24.2) | -0.66±1.54 | -0.47±1.72 |
| 5th | 106 (23.7) | -1.21±2.29 | -0.90±1.52 |
| 6th | 21 (4.7) | -0.51±1.14 | -0.70±1.05 |
| Mode of living | |||
| Urban | 187 (41.8) | -0.89±1.90 | -0.79±1.84 |
| Rural | 251 (56.2) | -0.93±1.79 | -0.76±1.54 |
| CGPA | |||
| Pass | 28 (6.3) | -0.82±1.79 | -0.86±1.74 |
| Good | 52 (11.6) | -1.39±2.63 | -0.94±1.73 |
| Very good | 219 (49.0) | -0.85±1.73 | -0.84±1.63 |
| Excellent | 121 (27.1) | -0.86±1.64 | -0.65±1.70 |
| Parental history of refractive error | |||
| None | 142 (31.8) | -0.82±1.69 | -0.64±1.45 |
| One | 109 (24.4) | -0.87±1.63 | -0.82±1.87 |
| Both of them | 107 (23.9) | -1.23±1.87 | -1.02±1.70 |
| Mobile use per day (h) | |||
| <4 | 103 (23.0) | -1.05±2.21 | -0.90±1.78 |
| 4-7 | 178 (39.8) | -0.82±1.50 | -0.66±1.70 |
| 8+ | 158 (35.3) | -0.96±1.93 | -0.87±1.58 |
| Video game (h) | |||
| <1 | 317 (70.9) | -1.01±1.82 | -0.91±1.77 |
| 1+ | 123 (27.5) | -0.66±1.85 | -0.45±1.29 |
| Total 95% CI | 447 (100) | -0.91±1.83 (-1.08, -74) | -0.78±1.67 (-0.93, -62) |
CI: Confidence interval, SD: Standard deviation, CGPA: Cumulative grade points average, SER: Spherical equivalent refraction
The prevalence of having any type of RE is presented in Table 2. The overall prevalence of REs was 48.8% (95% CI [44.2, −53.4]). The prevalence of REs among female medical students was 55.1% (95% CI [48.6, 61.5]), which was significantly higher than that among males (42.3%, 95% CI [36.0, 48.9]), with a P < 0.05. The prevalence of RE among students who play video games for <1 h was 53.9% (95% CI [48.4, 59.3]), compared with 36.6% (95% CI [28.6, 45.4]) among participants who play video games more than 1 h/day. REs did not differ significantly according to the rest of the factors presented in the table.
Table 2.
Prevalence of refractive errors regarding some selected characteristics
| Characteristic | RE+/total | Prevalence | 95% CI | P |
|---|---|---|---|---|
| Gender | ||||
| Male | 94/222 | 42.3 | 36.0-48.9 | 0.007 |
| Female | 124/225 | 55.1 | 48.6-61.5 | |
| Age groups (years) | ||||
| 18-21 | 51/102 | 42.5 | 34.0-51.5 | 0.054 |
| 21-23 | 136/252 | 54.0 | 47.8-60.0 | |
| 24-27 | 30/71 | 42.3 | 31.4-53.9 | |
| Study level (years) | ||||
| 2nd | 47/94 | 50.0 | 40.0-60.0 | 0.942 |
| 3rd | 55/118 | 46.6 | 37.8-55.6 | |
| 4th | 53/108 | 49.1 | 39.8-58.4 | |
| 5th | 54/106 | 50.9 | 41.5-60.3 | |
| 6th | 9/21 | 42.9 | 24.4-63.6 | |
| Mode of living | ||||
| Urban | 97/187 | 51.9 | 44.7-58.9 | 0.241 |
| Rural | 116/251 | 46.2 | 40.1-52.4 | |
| CGPA | ||||
| Pass | 16/28 | 57.1 | 38.9-73.6 | 0.169 |
| Good | 30/52 | 57.7 | 44.1-70.2 | |
| Very good | 104/219 | 47.5 | 41.0-54.1 | |
| Excellent | 55/121 | 45.5 | 36.8-54.3 | |
| Parental history of refractive error | ||||
| None | 60/142 | 42.3 | 43.4-50.0 | 0.050 |
| One | 58/109 | 53.2 | 43.9-62.3 | |
| Both of them | 61/107 | 57.0 | 47.5-66.0 | |
| Mobile use per day (h) | ||||
| <4 | 54/103 | 52.4 | 42.8-61.8 | 0.175 |
| 4-7 | 78/178 | 43.8 | 36.7-51.2 | |
| 8+ | 84/158 | 53.2 | 45.4-60.8 | |
| Video game (h) | ||||
| <1 | 171/317 | 53.9 | 48.4-59.3 | 0.001 |
| 1+ | 45/123 | 36.6 | 28.6-45.4 | |
| Overall prevalence | 218/447 | 48.8 | 44.2-53.4 | |
CI: Confidence interval, CGPA: Cumulative grade points average, RE: Refractive errors
The prevalence of students with myopia, hyperopia, and astigmatism was calculated and is shown in Table 3 broken down by some selected characteristics. Of the 447 medical students examined, approximately one-third (33.8%) had myopia, 10.5% had astigmatism, and only 10.5% had hyperopia. The table further showed that myopia is the most common RE among the medical students, and it differs significantly according to gender, parental history of RE, and duration of playing video games (P < 0.05 for all).
Table 3.
Pattern of refractive errors according to some selected characteristics
| Characteristic | Pattern of refractive errors | Emmetropia | P | ||
|---|---|---|---|---|---|
| Myopia | Hyperopia | Astigmatism | |||
| Gender | |||||
| Male | 59 (26.6) | 10 (4.5) | 25 (11.3) | 128 (57.7) | 0.015 |
| Female | 92 (40.9) | 10 (4.4) | 22 (9.8) | 101 (44.9) | |
| Age groups (years) | |||||
| 18-21 | 38 (31.7) | 2 (1.7) | 11 (9.2) | 69 (57.5) | 0.184 |
| 21-23 | 95 (37.7) | 14 (5.6) | 27 (10.7) | 116 (46.0) | |
| 24-27 | 18 (25.4) | 4 (5.6) | 8 (11.3) | 41 (57.7) | |
| Study level (years) | |||||
| 2nd | 35 (37.2) | 3 (3.2) | 9 (9.6) | 47 (50.0) | 0.106 |
| 3rd | 35 (29.7) | 3 (2.5) | 17 (14.4) | 63 (53.4) | |
| 4th | 37 (34.3) | 11 (10.2) | 5 (4.6) | 55 (50.9) | |
| 5th | 38 (35.8) | 3 (2.8) | 13 (12.3) | 52 (49.1) | |
| 6th | 6 (28.6) | 0 (0.0) | 3 (14.3) | 12 (57.1) | |
| Mode of living | |||||
| Urban | 63 (33.7) | 10 (5.3) | 24 (12.8) | 90 (48.1) | 0.373 |
| Rural | 85 (33.9) | 9 (3.6) | 22 (8.8) | 135 (53.8) | |
| CGPA | |||||
| Pass | 12 (42.9) | 2 (7.1) | 2 (7.1) | 12 (42.9) | 0.239 |
| Good | 19 (36.5) | 4 (7.7) | 7 (13.5) | 22 (42.3) | |
| Very good | 68 (31.1) | 7 (3.2) | 29 (13.2) | 115 (52.5) | |
| Excellent | 45 (37.2) | 3 (2.5) | 7 (5.8) | 66 (54.5) | |
| Parental history of refractive error | |||||
| None | 43 (30.3) | 7 (4.9) | 10 (7.0) | 82 (57.7) | 0.027 |
| One | 34 (31.2) | 7 (6.4) | 17 (15.6) | 51 (46.8) | |
| Both of them | 48 (44.9) | 2 (1.9) | 11 (10.3) | 46 (43.0) | |
| Mobile use per day (h) | |||||
| <4 | 36 (35.0) | 5 (4.9) | 13 (12.6) | 49 (47.6) | 0.622 |
| 4-7 | 53 (29.8) | 8 (4.5) | 17 (9.6) | 100 (56.2) | |
| 8+ | 61 (38.6) | 6 (3.8) | 17 (10.8) | 74 (46.8) | |
| Video game (h) | |||||
| <1 | 124 (39.1) | 15 (4.7) | 32 (10.1) | 146 (46.1) | 0.002 |
| 1+ | 26 (21.1) | 4 (3.3) | 15 (12.2) | 78 (63.4) | |
| Overall prevalence | 151 (33.8) | 20 (4.5) | 47 (10.5) | 229 (51.2) | |
CGPA: Cumulative grade points average
Table 4 presents the associations between myopia, hyperopia, and certain risk factors based on logistic regression models. The table showed that females were 52% more myopic than males (OR = 1.52, 95% CI [1.04, 2.22]) and that students with both parents having a history of RE were twofold more myopic than students with no family history of REs (OR = 2.01, 95% CI [1.2, 3.4]). A history of blurred vision also increases the risk of myopia by seven times (OR = 7.2, 95% CI [6.4, 11.3]). Increasing the distance from the TV is associated with a higher prevalence of myopia, as shown by the OR over unity (OR = 1.14, 95% CI [1.04, 1.3]). Using contact lenses was positively associated with hyperopia (OR = 2.1, 95% CI [1.02, 4.0]).
Table 4.
Associations of myopia/hyperopia in the medical students based on logistic regression models
| Factors | Myopia | Hyperopia | ||
|---|---|---|---|---|
| OR | 95% CI | OR | 95% CI | |
| Gender | ||||
| Male | 1 | 1 | ||
| Female | 1.52* | 1.04-2.22 | 1.5 | 0.71-3.1 |
| Family history | ||||
| None | 1 | |||
| One | 1.60 | 0.91-2.7 | 1.74 | 0.52-5.8 |
| Both of them | 2.01* | 1.2-3.4 | 0.56 | 0.22-1.35 |
| History of headache | ||||
| No | 1 | 1 | ||
| Yes | 1.27 | 0.87-1.8 | 1.18 | 0.57-2.44 |
| History of blurred vision | ||||
| No | 1 | 1 | ||
| Yes | 7.2 | 6.4-11.3 | 1.73 | 0.84-3.5 |
| Using contact lenses | ||||
| No | 1 | 1 | ||
| Yes | 1.30 | 0.85-1.1 | 2.1* | 1.02-4.0 |
| Mobile use per day | 0.96 | 0.92-1.0 | 1.06 | 0.96-1.16 |
| TV distance (m) | 1.14* | 1.04-1.3 | 0.93 | 0.82-1.04 |
| Average time video | 1.11 | 0.95-1.27 | 1.15 | 0.81-1.64 |
CI: Confidence interval, OR: Odds ratio
Of the 151 medical students who are classified as myopic, 76.3% had low myopia, 19.9% had moderate myopia, and only 3.9% had high myopia. According to gender, 79.0% of females and 72.8% of males had low myopia [Figure 1].
Figure 1.
Different levels of myopia according to gender
Discussion
REs are among the leading causes of vision loss worldwide.[2] Therefore, it has been the concern of numerous researches worldwide to determine the patterns of its prevalence among different populations and to determine the risk factors impacting its prevalence. The present study was conducted among medical students who are frequently more exposed to risk factors affecting their vision such as near work.
Our study revealed that about half of the students (48.8%) who participated in the study had a form of REs. Compared to the prevalence reported by previous studies, there was a great variation between different countries. Furthermore, the prevalence of RE varied between different groups within the same country [Table 5].
Table 5.
Prevalence of refractive errors among medical students in different countries
| Study | Sample size | Population-country | Prevalence (%) |
|---|---|---|---|
| Alsaif et al. 2019[14] | 338 | Imam Abdulrahman bin Faisal University-Saudi Arabia | 47.9* |
| Patel et al. 2019[10] | 248 | GMERS Medical College-India | 48.3 |
| Rizyal et al. 2019[15] | 210 | Nepal Medical College-Kathmandu Nepal | 51.4 |
| Shi et al. 2018[16] | 3654 | Tianjin Medical University-China | 89.93 |
| Alruwaili et al. 2018[8] | 278 | Aljouf University Medical Students-Saudi Arabia | 83.1 |
| Al-Rashidi et al. 2018[5] | 162 | Medical Students of Qassim University-Saudi Arabia | 53.7* |
| Alruwaili et al. 2018[17] | 167 | Northern Border University-Saudi Arabia | 67.1 |
| Algorinees 2017[18] | 504 | Hail University and Prince Sattam University-Saudi Arabia | 53.5* |
| Jyothirmai et al. 2017[30] | 361 | Andhra Medical College-Visakhapatnam | 70.7 |
| Salih 2017[19] | 330 | El-Mustansiriyah Medical Students-Iraq | 33 |
| Kshatri et al. 2016[20] | 506 | Medical College of Odisha-India | 54.5* |
| Basu et al. 2016[21] | 244 | Medical Student of Kolkata-India | 26.23 |
| Grigoras et al. 2016[22] | 576 | Medical students from “Grigore T. Popa” University of Medicine and Pharmacy-Romania | 73.8* |
| Parveen et al. 2015[23] | 500 | Liaquat National Medical College-Karachi Pakistan | 47* |
| Sharvani et al. 2015[24] | 100 | RIMS KADAPA-India | 32.24 |
| Dey et al. 2014[25] | 580 | Burdwan Medical College-India | 56.90 |
| Ahmed et al. 2014[9] | 419 | Medical Students of King Saud University-Saudi Arabia. | 44.4* |
| Krishnakumar et al. 2014[26] | 235 | Myopia and Digit Ratio in Medical College Students-India | 54* |
| Megbelayin et al. 2014[27] | 83 | Nigerian MedicalSchool-Nigerian | 79.5 |
| Rajdeep and Patel 2013[28] | 283 | Baroda Medical College - India | 54.06% |
| Gopalakrishnan et al. 2011[12] | 425 | AIMST University - Malaysia | 32.24% |
*The prevalence in those studies was based only on myopia
The prevalence revealed by the present study was lower than those previously reported in some districts of Saudi Arabia (Aljouf and Northern Border Universities).[8,17] It was also lower than what was reported in China, Romania, Nigeria, and Andhra Medical College in India.[3,16,22,27] However, it was higher than the prevalence recorded in other parts of India.[21,24] It was also higher than the prevalence observed in Iraq and Malaysia.[12,19]
Nevertheless, several studies reported a similar prevalence to that of our study including studies conducted in Saudi Arabia (in Dammam, Qassim, Hail, and Riyadh),[5,9,14,18] India, Pakistan, and Nepal.[10,15,20,23,25,26,28] Those variations in prevalence could be related to differences in lifestyle, socioeconomic status, and environmental factors.
Furthermore, the present study showed that myopia was the most common type of REs, affecting one-third (33.8%) of the students compared to hyperopia and astigmatism. While other studies conducted in the KSA agreed that myopia was the most common type of REs among students,[5,8,9] they reported a higher prevalence of myopia than our study.
Regarding hyperopia and astigmatism, our study revealed that 10.5% of the students had hyperopia and 10.5% had astigmatism. These percentages are higher compared to those previously reported by Al-Rashidi et al. in Qassim, who reported that only 3.7% of the students had hyperopia and only 1.2% had astigmatism.[5] Similarly, Alruwaili et al. reported a low prevalence of hyperopia (3.5%) and a significantly higher prevalence of astigmatism (53.7%) among Aljouf students.[8]
Regarding the RE risk factors, our results showed that family history is a major risk factor for myopia, by twofold, as had also been found among students of Hail University and Prince Sattam University.[18] In agreement with results from King Saud University, we found that females were more affected than males.[9]
Our results also revealed a strong association between TV distance and myopia, with a larger distance being associated with a higher risk of having myopia, which is completely different from what was documented in Jazan.[29] However, usage of electronic devices was insignificant in our study, which was clearly shown in GMERS University in India.[10] We also found that wearing contact lenses is associated with hyperopia, while in another study in Saudi Arabia, they found that it was associated with myopia.[18] However, age was insignificant in our findings, unlike what was previously reported in Hail University and Prince Sattam University study.[18]
While conducting our study, we came across some limitations. First, the study is based on a cross-sectional study design; therefore, temporal associations cannot be properly established. The second limitation of the study was the short timetable to collect our data. In addition, collecting the data while students attend their lectures or take exams affected their participation in the study. Finally, since we used an autorefractor test to measure the REs among students, the results were objective rather than subjective.
Conclusion
REs, mainly myopia, were highly prevalent among medical students at Jazan University, Saudi Arabia. Female students were more affected than male students. We recommend increasing awareness among medical students of RE and carrying out screening programs to early detect and correct RE to prevent future vision problems.
Financial support and sponsorship
This research project was funded by the Deanship of Scientific Research at Jazan University (Project number FS10-057).
Conflicts of interest
There are no conflicts of interest.
Acknowledgments:
We would like to thank the Future Scientist Program, Deanship of Scientific Research, Jazan University, for the financial support of this study. We are also highly indebted to the study participants, who sacrificed their time and participated in this research. Special thanks to Al-Ihsan Medical Mobile Eye Clinic, Rafaa Alsharif, Mazen Hakami, Fatimah Albeladi, and Reham Ajeebi for their support in the data collection process.
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