Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
ORIGINAL ARTICLE  
Effect of Binocular Vision Problems on  
Childhood Academic Performance and  
Teachers’ Perspectives  
Saif Hassan Alrasheed1,2, Abd Elaziz Mohamed Elmadina1,2  
1 Department of Optometry College of Applied Medical Sciences, Qassim University, Saudi Arabia  
2 Faculty of Optometry and Visual Sciences, Al-Neelain University, Khartoum, Sudan  
ABSTRACT  
Purpose: To see the effect of binocular vision problems on childhood academic performance and  
to record the teacher's perspectives about childhood eye care in Khartoum State of Sudan.  
Place and Duration of Study: A descriptive cross-sectional study done among the school going  
children in the Khartoum State of Sudan from February to May, 2018.  
Study Design: Descriptive cross sectional study.  
Material and Methods: Three hundred and forty (340) primary school children were recruited  
for study by convenient sampling technique during the academic year 2018. After relevant history,  
ocular examination was performed. It included visual acuity measurement, assessment of  
refractive errors and binocular function tests. Academic performance of the children was  
recorded from academic records of the children. Finally, the qualitative data was derived from  
teachers’ perspectives about childhood eye care.  
Results: Mean age of the participants was 11.96 ± 1.63 years. The findings revealed that (78.6%)  
of children achieved poor academic performances with decompensated exophoria at near. 52.7%  
children with poor academic performances had weak positive fusion reserve at near P = 0.04.  
37.2% of the poor performers had convergence insufficiency. Forty-eight percent of females with  
ocular complaints achieved poor academic performances P = 0.034. With regard to teacher's  
perspectives about childhood eye care, 98.8%believed that the vision problems had effect on the  
academic record of the children. Seventy percent of the teachers reported that the students did  
not undergo eye examinations before joining school.  
Conclusion: Convergence Insufficiency and weak positive fusional reserve at near has a significant  
effect on academic performances.  
Key Words: Convergence Insufficiency, Binocular vision, Exophoria.  
How to Cite this Article: Alrasheed SH, Elmadina AEM. The Effect of Binocular Vision Problems  
on Childhood Academic Performance and Teachers’ Perspectives. Pak J Ophthalmol. 2020, 36 (2):  
163-168.  
Doi: 10.36351/pjo.v36i2.  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
Correspondence to: Saif Hassan Al-Rasheed  
Assistant Professor, Department of  
Optometry College of Applied Medical  
Sciences, Qassim University, Saudi Arabia. E-  
mail: saif.alrasheed@yahoo.com  
secondary school-children in Sudan was  
7.8%12. Phillips in 201713 revealed that  
Patients with CI had symptoms during  
activities that required near fixation, such as  
reading. Thus, CI was associated with  
reading impairment and could lead to poor  
academic performance.  
INTRODUCTION  
Childhood vision problems are different in  
nature and severity, ranging from mild  
refractive errors to binocular anomalies and  
vision impairment. Many vision problems  
lead to a variety of symptoms that greatly  
affect skills of learning1. The most common  
vision problems are uncorrected refractive  
errors that impair vision at distance (myopia)  
or at near (hypermetropia); these are often  
treatable with spectacles or contact lenses.  
Other important vision problems include  
astigmatism, strabismus (latent or manifest),  
amblyopia (lazy eye), problems with  
binocular coordination of eye movements,  
and problems with the integration of visual  
sensory perception and the brain. These  
problems could be avoided with eyeglasses,  
medication, or vision therapy2-5. Basch, 2011  
reported that more than 20% of school going  
have some kind of vision problem6. In a  
nationally representative sample of more  
than 48,000 students under age 18, those  
from poor families were less likely to have  
diagnosed eye problems than the children  
living in higher income families.  
As mentioned above from the previous  
study, the vision problems (refractive errors,  
binocular anomalies and amblyopia) are  
more prevalent among school going children  
in Sudan. The rates of vision problems  
increase with the increasing age of children.  
Vision related problems among school going  
children have great effect on childhood  
academic performances in school or at any  
work achievements and have a negative  
influence on the future of the children  
The current study was conducted to assess  
the effect of binocular vision problems on  
childhood academic performance and  
teacher's perspectives about childhood eye  
care in Khartoum State of Sudan.  
MATERIAL AND METHODS  
This cross-sectional school-based study,  
which was conducted among school going  
children in Khartoum State of Sudan, aimed  
to assess the effect of binocular vision  
problems  
on  
childhood  
academic  
performances and teachers’ perspectives  
about childhood eye care.  
Uncorrected refractive errors drive children  
into poverty by limiting their opportunities  
to education, and employment, and can  
seriously affect their quality of life and  
academic productivity7-10. In a recent study  
conducted by Al-Rasheed, et al11 to assess  
the Visual Impairment (VI) and Refractive  
Error (RE) among Sudanese school going  
children, revealed that the most common  
cause of VI was uncorrected RE (57%) and  
amblyopia was 5.6%. They reported that  
prevalence of exophoria at near fixation was  
46.9%. In another study by Hassan, et al, it  
was they reported that the prevalence of  
Convergence Insufficiency (CI) among  
The study used a convenience sample of four  
public primary schools located in the Centre  
of Khartoum city (two schools for males and  
two schools for females). The study was  
performed in the academic year 2018 from  
February to May. Before data collection the  
primary schools selected for the study were  
visited by the researchers to explain the aim  
of the study to the school administration,  
and children were given requests for  
informed consent of their parents to allow  
them to participate in the study. All the  
children from grade three to grade eight  
attending the school on days of  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
examinations, after their parents’ signed  
informed consent and the children, agreed  
to participate were included in the study.  
Three hundred forty school-going children  
fulfilled the criteria of this study.  
RESULTS  
In addition to 340 children from four schools  
(two male schools and two female schools),  
80 school teachers were also included in this  
study. The sample consisted of 191 (56.0%)  
males and 149 (44%) females, with a mean  
age of 11.96 ± 1.63 years. Most of the  
students 61.2% presented without ocular  
symptoms χ2 = 656.18, p < 0.0001, 15.9%  
complained of blurred vision, followed by  
12.0% and 5.9% of children complained of  
headache and ocular pain respectively. With  
regard to the relationship between  
academic performances of children and  
ocular complaints, majority of the students  
with excellent academic performance were  
without ocular complaints. However, only  
21.0% and 13.2% of children who  
complained of blurred vision and headache  
respectively, achieved excellent academic  
performance. Sixty-four percent children  
without any ocular complaints had poor  
academic performance χ2 = 55.18, p <  
0.0001. However, 14.5% and 9.2% of  
children who complained of blurring vision  
and headache respectively achieved poor  
academic performance. The Spearman's rho  
correlation revealed very strong correlation  
(r = 0876, p = 0.008) between academic  
performance of children and ocular  
complaints as showed in table 1.  
Optometric research assistants graduated  
from the school of optometry and with  
experience in clinical optometry were  
recruited to assist in data collection. The  
data collector underwent training in the  
study protocol procedures. The principal  
investigator explained the procedures for  
gathering the clinical data from the children  
as well as qualitative information from 80  
schoolteachers.  
Visual Acuity (VA) of the participants at  
distance was assessed using Snellen  
tumbling E-chart with E's of standard size  
from a 6-meter distance. Amplitude of  
accommodation and near point of  
convergence was measured using RAF Rule.  
Prism cover test was performed at 33 cm for  
near fixation and for 6-meter distance  
fixation, the subjects fixed above the line of  
thresholds of poor eye to assess the degree  
of heterophoria and heterotropia. The  
subjects underwent motility tests to assess  
the function of eye muscles; objective  
refraction was assessed using retinoscopy  
(Neitz RX, Japan). The positive and negative  
fusional reserve was measured with prism  
bar at 33 cm and 6 – meter for near and  
distance respectively. The academic  
performance of the children was obtained  
from the files that recorded the final  
examination of the last year. Finally, the  
qualitative data about the Knowledge of  
childhood eye care was collected from  
school teachers by a completed semi-  
structural questionnaire. The data was  
analysed using Statistical Package for Social  
Science (SPSS version 25, Armonk, NY: IBM  
Corp USA). Descriptive statistics was used to  
Fifty-one percent of females were free from  
ocular complaints, 43.3% complained of  
(blurred vision, ocular pain, difficulty in  
fixation, photophobia, tearing and itching).  
The relationship between academic  
performance of female children and ocular  
complaints was statistically significant χ2 =  
0.127; p = 0.034 as shown in table 2. The  
study found that 66.7% of the males without  
ocular complaints had excellent academic  
performances. The association between  
academic performance of male children and  
ocular complaints was not statistically  
significant χ2 = - 0.034; p = 0.645 as shown in  
table 2. The relationship between academic  
describe  
data.  
For  
all  
statistical  
determinations, the significance level was  
established at P < 0.05.  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
performances of children and vision was not  
statistically significant χ2 = - 0.034; p = 0.645  
as shown in table 3. The relationship  
between academic performance of children  
and refractive errors was statistically not  
significant (χ2 = 23.172; p = 0.335). Seventy-  
eight percent children with poor academic  
performance had exophoria, followed by  
8.4% having esophoria and 0.8%with tropias.  
The relationship between academic  
performances of children and ocular  
deviation at near was statistically significant  
(χ2 = 3.578; p = 0.014) as shown in table 4.  
the distance visual acuity did not play a  
significant role in predicting academic school  
performance18. They concluded that most of  
the reading and writing activities needed  
good near vision and near binocular  
functions.  
Our findings also endorse the results of  
Chen, at el19, who concluded that children  
with low academic achievement were more  
likely to exhibit problems in ocular motor  
balance. Our results that convergence  
insufficiency (CI) was more common among  
females than males was in agreement with  
study by Hassan, et al12 in Sudan who  
reported that CI was common among school  
going children. Scheiman, et al20, reported  
that after treatment of CI statistically  
significant improvements were found for  
reading activities. Near activities like  
reading, writing and watching need good  
positive fusional reserve (PFR) and the  
children with weak PFR find difficulties in  
concentration for long time. There is a  
chance that children with poor fusional  
reserve may become symptomatic when  
attempting near task; their heterophoria  
may become uncontrollable and lead to  
heterotropia.  
Seventy-three percent children with  
excellent academic performances had  
normal near point of convergence (NPC);  
however, only 26.3% of children with  
abnormal NPC had excellent academic  
performance. The relationship between  
academic performance of children and NPC  
was statistically not significant (χ2 = 2.05; p =  
0.562). Chi square test revealed significant  
difference between academic performance  
of children and positive fusion at near (χ2 =  
5.684; p = 0.042) as shown in table 5.  
DISCUSSION  
Alrasheed et al10 indicated that knowledge  
about childhood eye care was low among  
the community. They concluded that, there  
was a need for structured educational  
program to raise awareness about childhood  
eye disease and visual impairment in order  
to address the barriers for accessing  
childhood eye care in Sudan. This can lead to  
early diagnosis and treatment of eye  
problems in children. As the most common  
cause of vision problem in children was  
uncorrected refractive error it can be easily  
corrected if discovered early7,9,21,22. We  
found in our study that  
Good vision and binocular functions are  
important for achieving high academic  
performance. In fact, many authors14-16  
reported that children with good vision and  
binocular functions could perform better in  
learning activity. Therefore, good visual  
functions are cornerstone for the students in  
all learning stages to achieve good academic  
performances  
Our results were in accordance with Shin, et  
al17, who found a significant relationship  
between symptomatic children with  
binocular vision problems and their scores in  
every academic area (reading, mathematics,  
social science, and science).  
A study  
conducted in Singapore to assess the effect  
of distance visual acuity on the academic  
achievements of children, concluded that  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
Table 1: The relationship between academic performance of children and ocular complaints.  
Symptoms  
Academic performance of participant  
Total N (%)  
Excellent N(%)  
V Good N (%)  
Good N (%)  
Poor N (%)  
Normal  
22(57.9)  
5(13.2)  
8 (21.0)  
2 (5.3)  
0 (0.0)  
1 (2.3)  
0 (0.0)  
48 (66.6)  
12 (16.6)  
9 (12.5)  
0 (0.0)  
54(54.5)  
12(12.1)  
18(18.2)  
9(9.1)  
84(64.1)  
12 (9.2)  
19 (14.5)  
9 (6.9)  
208(61.2)  
41(12.0)  
54(15.9)  
20(5.9)  
3(0.9)  
Headache  
Blur of vision  
Ocular pain  
Difficult fixation  
Photophobia  
Tearing and itching  
0 (0.0)  
2 (2.0)  
1 (0.7)  
2 (2.7)  
0 (0.0)  
4 (4.0)  
1 (0.7)  
4(1.2)  
1 (1.3)  
5 (3.8)  
10(2.0)  
Total  
38 (100)  
72 (100)  
99(100)  
131(100  
340(10)  
χ2 = 19.9  
p = 0.008  
Table 2: Relationship between academic performance of male and female children and ocular  
complaints.  
Symptoms  
Academic performance of Females participant  
Total N (%)  
Excellent N (%)  
12(52.0)  
11(48.0)  
23(100)  
V Good N (%)  
22(66.7)  
11(33.3)  
33(100)  
Good N (%)  
21(42.0)  
29(58.0)  
50(100)  
Poor N (%)  
22(51.2)  
21(48.8)  
43(100)  
Normal  
Ocular Complaints  
Total  
77(51.7)  
72(48.3)  
149(100)  
Symptoms  
Academic performance of Males participant  
Total N (%)  
Excellent N (%)  
10(66.7)  
5(33.3)  
15(100)  
V Good N (%)  
26(66.7)  
13(33.3)  
39(100)  
Good N (%)  
33(67.30)  
16(32.7)  
Poor N (%)  
62(70.5)  
26(29.5)  
88(100)  
Normal  
Ocular complaints  
Total  
131(68.6)  
60(31.4)  
191(100)  
49(100)  
Table 3: Relationship between vision of participants and academic performance.  
Vision  
Academic performance of participant  
Total N (%)  
Excellent N(%)  
31(81.6)  
7(18.4)  
V Good N (%)  
63(87.5)  
9(12.5)  
Good N (%)  
82(82.0)  
18(18.)  
Poor N (%)  
112(85.5)  
19(14.5)  
Normal  
VI  
Total  
288(84.7)  
52(15.3)  
340(100)  
38(100)  
72(100)  
99(100)  
131(100)  
V I= Vision Impairment ≤ 6/12  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
Table 4: The effect of ocular deviation on academic performance of school going children  
Ocular deviation  
Academic performance of participant  
Excellent N(%) V Good N (%) Good N (%)  
Total N (%)  
Poor N (%)  
16(12.2)  
103(78.6)  
11(8.4)  
Orthophoria  
Exophoria  
Esophoria  
Tropia  
30(78.9)  
5(13.2.)  
3 (7.9)  
51(70.8)  
17(23.6)  
4 (5.6)  
38(38.4)  
55(55.5)  
5(5.1)  
135(39.7)  
180(52.9)  
23(6.8)  
0 (0.0)  
0 (0.0)  
1(1.0)  
1(0.8)  
2(0.6)  
Total  
38(100)  
72(100)  
99(100)  
131(100)  
340(100)  
Table 5: Relation of Positive Fusional vergence and Academic performance of participant  
Positive fusional  
Academic performance of participant  
Total N(%)  
Vergence  
Excellent N (%)  
V Good N (%)  
38(52.8)  
Good N (%)  
Poor N (%)  
61(47.2)  
Normal(30-45)  
Abnormal(2-25)  
Total  
26(68.4)  
12(31.6)  
38(100)  
52(52.5)  
47(47.5)  
99(100)  
177(52.4)  
161(47.6)  
338(100)  
34(34.3)  
68(52.7)  
72(100)  
129(100)  
Table 6: Teachers Knowledge and Practice about childhood eye care.  
Question  
Yes N(%) No N (%)  
Total  
Q1: Do you the think vision problem has effect on the academic achievement  
Q2: Are teachers attending any course for identifying childhood eye problems :  
79 (98.8)  
11(13.8)  
1(1.3)  
80(100%)  
80(100%)  
80(100%)  
69(86.3)  
3(3.8)  
Q3: Do teachers inform the student guardian/parents about the childhood eye 77(96.3)  
problems  
Q4: Are teachers have knowledge to identify the children with vision problem in 78(97.5)  
classroom  
2(2.5)  
5(6.3)  
80(100%)  
80(100%)  
Q5: If there special treatment for the student who have vision impairment in class 75(93.8)  
room  
Q6: Do you think the size of print in the books is suitable for reading  
Q7: Are the students undergo eye examinations when joining the school  
Q8: There is annual comprehensive eye examination for children  
53(66.3)  
24(30)  
27(33.8)  
56(70)  
80(100%)  
80(100%)  
80(100%)  
80(100%)  
80(100%)  
29(36.3)  
51(63.7)  
23(28.7)  
9(11.3)  
Q9: Do you think that increasing the number of home work hours causes eye strain 57(71.3)  
Q10: Do you think that eye fatigue is increased during the examinations period  
71(88.8)  
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 163-168  
Saif Hassan Alrasheed, et al. The Effect of Binocular Vision Problems on Childhood Academic  
Performance and Teachers’ Perspectives  
Most of teachers (98.8%)were aware of the  
fact that vision problems had effects on the  
academic achievement of students, whereas  
only 1.3% of teachers believed that vision  
problems did not affect the academic  
performance of the students. Almost 86.3%  
of teachers reported that they did not attend  
any course for identifying childhood eye  
problems, whereas 13.8% of school teachers  
were attending courses for identifying  
childhood eye problems. Ninety-six percent  
of teachers had informed the students’  
guardians/parents about the eye problems  
of the children whereas 3.8% did not. Most  
of teachers (97.5%) reported that they had  
knowledge to identify children with vision  
impairment in classroom while 2.5% did not.  
There were 93.8% teachers, who provided  
special management to the students with  
poor vision. More than half (66.3%) of school  
teachers thought that the size of print in the  
books was suitable for reading, however  
33.8% of teachers believed that the size of  
print in the books was not suitable for  
reading. Seventy-one percent teachers had  
concern about the increasing numbers of  
homework hours, which could lead to eye  
strain (table 6).  
Doa Ali, Emtithal Gamal and Rowiada Jadin  
for their help in data collection. We would  
also like to thank all the students and  
teachers who participated in this study.  
Ethical Approval  
The study was approved by the Institutional  
review board/Ethical review board.  
Conflict of Interest Authors declared no  
conflict of interest.  
Authors’ Designation and Contribution  
Dr. Saif Hassan Al-Rasheed; Assistant  
Professor Optometry: Data collection, data  
analysis, manuscript writing, final review.  
Dr. Abd Elaziz Mohamed Elmadina;  
Assistant Professor Optometry:  
Data collection, data analysis, final review.  
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