Prevalence and associated factors of myopia among high school students in Gondar town, northwest Ethiopia, 2016

Figures & data

Figure 1 Schematic presentation of sampling procedure.

Table 1 Sociodemographic characteristics of study participants among high-school students in Gondar town, northwest Ethiopia, 2016

Variables	Frequency (%)
Age category
15–17 years	150 (30.3)
18–19 years	218 (44.0)
20–22 years	127 (25.7)
Age at start of formal school
3–6 years	244 (49.3)
7 years	152 (30.7)
8–9 years	99 (20.0)
Sex
Female	257 (51.9)
Male	238 (48.9)
School type
Government	432 (87.3)
Private	63 (12.7)
Religion
Ethiopian orthodox	425 (85.9)
Muslim	44 (8.9)
Protestant	16 (3.2)
Catholic	10 (2.0)
Parental education status
Unable to write and read	95 (19.2)
Able to read and write	134 (27.1)
Primary school	58 (11.7)
Secondary school	96 (19.4)
College/university	112 (22.6)

Table 2 Proportion of myopia, familial myopia, and ocular abnormalities among study participants in Gondar town, northwest Ethiopia, 2016

Variables	Frequency (%)
Myopia (n=495)
Yes	59 (11.9)
No	436 (88.1)
Degree of myopia (n=495)
Low	40 (8.1)
Moderate	15 (3.0)
High	4 (0.81)
Ocular abnormality (n=495)
Yes	68 (86.3)
No	427 (13.7)
Familial myopia (n=495)
No family history	411 (83.0)
History in one family member	49 (9.9)
History in more than one family member	35 (7.1)

Table 3 Factors associated with myopia of study participants among high-school students, Gondar town, northwest Ethiopia, 2016

Variables	Myopia		Crude odds ratio (95% CI)	Adjusted odds ratio (95% CI)
	Yes	No
Sex*
Male	16	222	1.00
Female	43	214	2.79 (1.52, 5.10)
School type
Government	46	386	1.00	1.00
Private	13	50	2.18 (1.10, 4.31)	2.88 (1.02, 8.11)**
Duration of schooling*
9–10 years	13	148	1.00
11–12 years	34	215	1.80 (0.91, 3.52)
>12 years	12	73	1.87 (0.83, 4.30)
Family history
No	27	384	1.00	1.00
Yes	32	52	13.43 (6.22, 28)	8.08 (4.30, 15.16)***
Time spent in indoor activities
<3 hours/day	12	145	1.00	1.00
3–8 hours/day	12	160	0.90 (0.40, 2.08)	0.91 (0.33, 2.51)
9–11 hours/day	24	88	3.30 (1.57, 6.92)	4.31 (1.69, 10.99)**
>11 hours/day	11	43	09 (1.27, 7.50)	2.43 (0.75, 7.84)
Ocular abnormalities
No	33	394	1.00	1.00
Yes	26	42	7.40 (4.03, 13.52)	6.69 (3.43, 13.03)***
Time spent for near work
<3 hours/day	10	164	1.00	1.00
3–8 hours/day	13	165	1.29 (0.55, 3.03	0.85 (0.32, 2.22)
9–11 hours/day	21	59	5.84 (2.60, 13.11)	2.89 (1.12, 7.43)**
>11 hours/day	15	48	5.12 (2.16, 12.14)	1.98 (0.66, 5.98)
Time spent in outdoor activities*
<3 hours/day	23	128	0.88 (0.39, 1.98)
3–8 hours/day	13	139	0.46 (0.191, 11)
9–11 hours/day	13	120	0.53 (0.22, 1.29)
>11 hours/day	10	49	1.00
Outdoor sport activities
No	45	234	2.77 (1.48, 5.20)	2.27 (1.05, 4.90)**
Yes	14	202	1.00	1.00
Working distance
<33 cm	32	72	5.23 (2.59, 10.56)	3.06 (1.33, 7.06)**
33–60 cm	14	211	0.78 (0.36, 1.70)	0.49 (0.18, 1.20)
>60 cm	13	153	1.00	1.00
Active rest during studying*
No	22	116	1.64 (0.30, 2.90)
Yes	37	320	1.00
Type of illumination*
Candle	12	54	2.73 (1.19, 6.26)
Table light	13	68	2.35 (1.05, 5.25)
Dim light	20	142	73 (0.84, 3.55)
Fluorescent/lamp	14	172	1.00
Visual display unit use
No	17	191	1.00	1.00
Yes	42	245	1.93 (1.06, 3.49)	2.81 (1.96, 6.10)**

Notes:

* Nonsignificant,

** p-value <0.05,

*** p-value <0.001.

Abbreviation: CI, confidence interval.