Table 1Unintentional Injury at School according to Sleep and Other Variables among Adolescents in Korea (N=63,307)
Variables |
Categories |
Injured |
No injured |
x2
|
p
|
n† (%)‡
|
n† (%)‡
|
Total |
|
29,508 (46.4) |
33,799 (53.6) |
|
|
Gender |
Male |
15,511 (48.6) |
16,105 (51.4) |
138.20 |
<.001 |
Female |
13,997 (44.0) |
17,694 (56.0) |
Grade |
7 |
5,195 (51.0) |
5,053 (49.0) |
770.98 |
<.001 |
8 |
5,541 (53.9) |
4,738 (46.1) |
9 |
5,398 (50.8) |
5,149 (49.2) |
10 |
4,517 (41.8) |
6,164 (58.2) |
11 |
4,578 (43.2) |
6,052 (56.8) |
12 |
4,279 (39.1) |
6,643 (60.9) |
School type |
Boys only |
5,334 (49.2) |
5,379 (50.8) |
180.92 |
<.001 |
Girls only |
4,634 (40.9) |
6,550 (59.1) |
Both |
19,540 (47.1) |
21,870 (52.9) |
Perceived economic status |
Upper |
9,678 (49.5) |
10,079 (51.0) |
91.94 |
<.001 |
Middle |
13,684 (44.7) |
16,675 (55.3) |
Lower |
6,146 (46.1) |
7,045 (53.9) |
Father's education level (year) |
≤9 |
1,072 (45.1) |
1,285 (54.9) |
55.69 |
<.001 |
10~13 |
9,563 (45.0) |
11,454 (55.0) |
≥14 |
13,388 (47.9) |
14,356 (52.1) |
Unknown |
4,238 (44.7) |
5,238 (55.3) |
Mother's education level (year) |
≤9 |
989 (45.2) |
1,220 (54.8) |
97.73 |
<.001 |
10~13 |
12,024 (44.8) |
14,540 (55.2) |
≥14 |
11,185 (48.8) |
11,623 (51.2) |
Unknown |
4,096 (44.4) |
5,131 (55.6) |
Number of physical education per week |
0 |
4,324 (35.5) |
7,603 (64.5) |
1,003.46 |
<.001 |
1 |
5,102 (44.7) |
6,261 (55.3) |
2 |
8,483 (46.2) |
9,702 (53.8) |
3 |
11,599 (53.5) |
10,233 (46.5) |
Current smoking |
Yes |
7,034 (52.1) |
6,401 (47.9) |
221.35 |
<.001 |
No |
22,474 (44.8) |
27,398 (55.2) |
Alcohol consumption |
Yes |
14,078 (50.3) |
13,775 (49.7) |
298.93 |
<.001 |
No |
15,430 (43.4) |
20,024 (56.6) |
Sleep duration (hour/day) |
<5 |
3,877 (46.0) |
4,538 (54.0) |
22.30 |
.017 |
5 |
6,097 (45.5) |
7,174 (54.5) |
6 |
7,302 (46.1) |
8,402 (53.9) |
7 |
7,252 (47.8) |
7,871 (52.2) |
8 |
3,897 (46.7) |
4,468 (53.3) |
9 |
931 (44.1) |
1,182 (55.9) |
≥10 |
152 (49.5) |
164 (50.5) |
Relief of fatigue after sleep |
Very enough |
1,724 (40.4) |
2,542 (59.6) |
199.44 |
<.001 |
Enough |
5,127 (43.4) |
6,507 (56.6) |
So-so |
9,173 (45.5) |
11,058 (54.5) |
Not enough |
9,221 (48.8) |
9,529 (51.2) |
Never enough |
4,263 (50.1) |
4,163 (49.9) |
Table 2Logistic Regression Analysis of Relationship between Sleep hours, Relief of Fatigue after Sleep and Injury Risk
Variables |
Adjusted OR†
|
95% CI |
Sleep hours (ref : 9hr) |
|
|
<5 |
1.74 |
1.53~1.98 |
5 |
1.61 |
1.43~1.83 |
6 |
1.45 |
1.28~1.63 |
7 |
1.31 |
1.16~1.47 |
8 |
1.13 |
1.01~1.27 |
≥10 |
1.40 |
1.03~1.91 |
Relief of fatigue after sleep (ref : very enough) |
|
|
Enough |
1.17 |
1.08~1.28 |
So-so |
1.36 |
1.26~1.47 |
Not enough |
1.63 |
1.50~1.77 |
Never enough |
1.77 |
1.62~1.95 |