Table 1.

Study population demographics

Variables, N (%)	No myopia 35,326 (58.1%)	Myopia 25,463 (41.9%)	Total 60,789 (100.0%)	P-value
Age at eye examination				<0.001
5 to <8 years	8,929 (25.3%)	1,548 (6.1%)	10,477 (17.2%)
8 to <11 years	9,610 (27.2%)	4,661 (18.3%)	14,271 (23.5%)
11 to <14 years	8,132 (23%)	7,941 (31.2%)	16,073 (26.4%)
14 to <17 years	7,486 (21.2%)	9,633 (37.8%)	17,119 (28.2%)
17 to <20 years	1,169 (3.3%)	1,680 (6.6%)	2,849 (4.7%)
Sex				0.718
Female	19,032 (53.9%)	13,756 (54%)	32,788 (53.9%)
Male	16,294 (46.1%)	11,707 (46%)	28,001 (46.1%)
Race				<0.001
White	14,567 (41.2%)	8,337 (32.7%)	22,904 (37.7%)
African American	3,740 (10.6%)	2,362 (9.3%)	6,102 (10.0%)
Asian/Pacific Islander	3,000 (8.5%)	4,570 (17.9)	7,570 (12.5%)
Other/Multiple/Unknown	14,019 (39.7%)	10,194 (40.0%)	24,213 (39.8%)
Ethnicity				<0.001
Not Hispanic	14,873 (42.1%)	11,695 (45.9%)	26,568 (43.7%)
Hispanic	20,453 (57.9%)	13,768 (54.1%)	34,221 (56.3)
Neighborhood household income (USD)				<0.001
Less than $25,000	710 (2.5%)	568 (2.7%)	1,278 (2.6%)
$25,000–49,999	9,328 (33.4%)	6,445 (31.1%)	15,773 (32.4%)
$50,000–99,999	14,896 (53.3%)	11,001 (53.1%)	25,897 (53.2%)
$100,000 or higher	3,018 (10.8%)	2,705 (13.1%)	5,723 (11.8%)
Body mass index percentile for age and sexa				0.763
Normal or under weight (<85th)	20,367 (60.4%)	14,238 (60.1%)	34,605 (60.3%)
Overweight (85th to <95th)	6,112 (18.1%)	4,340 (18.3%)	10,452 (18.2%)
Moderately obese (95th–1.2 × 95th)	6,634 (19.7%)	4,394 (18.5%)	11,028 (19.2%)
Extremely obese (≥1.2 × 95th)	630 (1.9%)	718 (3.1%)	1,348 (2.3%)
Exercise per day				<0.001
Less than 60 min	14,685 (59.6%)	11,114 (65.0%)	25,799 (61.8%)
At least 60 min	9,957 (40.4%)	5,986 (35.0%)	15,943 (38.2%)

Note:

^aBased on the sex-specific body mass index-for-age growth charts developed by the Centers for Disease Control and Prevention.²⁵