Table 1 Characteristics of children included in the study and children lost to follow-up between 18 monthsand seven years old (n = 32,407).
From: A nationwide longitudinal survey of infantile injury and its recurrence in Japan
Included | Lost to follow-up | |||
|---|---|---|---|---|
(n = 20,191) | (n = 12,216) | |||
Injuries at 18 months, n (%) | ||||
None | 3,952 | (19.6) | 3,264 | (26.7) |
Yes | 16,239 | (80.4) | 8,952 | (73.3) |
Sex, n (%) | ||||
Male | 10,626 | (52.6) | 6,097 | (49.9) |
Female | 9,565 | (47.4) | 6,119 | (50.1) |
Term or Preterm Birth, n (%) | ||||
Term | 19,133 | (94.8) | 11,560 | (94.6) |
Preterm | 1,058 | (5.2) | 656 | (5.4) |
Singleton or Multiple Birth, n (%) | ||||
Singleton | 19,829 | (98.2) | 11,993 | (98.2) |
Multiple | 362 | (1.8) | 223 | (1.8) |
Birth Order, n (%) | ||||
1 | 9,637 | (47.7) | 5,622 | (46.0) |
2 | 7,765 | (38.5) | 4,442 | (36.4) |
3 or more | 2,789 | (13.8) | 2,152 | (17.6) |
Daycare Attendance, n (%)b | ||||
Home | 14,708 | (72.8) | 8,724 | (71.4) |
Nursery | 5,480 | (27.1) | 3,487 | (28.5) |
Missing | 3 | (0.0) | 5 | (0.0) |
Maternal Age at Delivery, n (%) | ||||
< 25 years old | 1,202 | (6.0) | 1,452 | (11.9) |
25–30 | 5,393 | (26.7) | 3,600 | (29.5) |
30–35 | 7,954 | (39.4) | 4,361 | (35.7) |
> 35 | 5,642 | (27.9) | 2,803 | (23.0) |
Maternal Smoking, n (%)a | ||||
None | 19,361 | (95.9) | 11,091 | (90.8) |
Yes | 786 | (3.9) | 1,092 | (8.9) |
Missing | 44 | (0.2) | 33 | (0.3) |
Paternal Smoking, n (%)a | ||||
None | 12,623 | (62.5) | 6,468 | (52.9) |
Yes | 7,268 | (36.0) | 5,414 | (44.3) |
Missing | 300 | (1.5) | 334 | (2.7) |
Maternal Education, n (%)b | ||||
University or Higher | 6,061 | (30.0) | 2,535 | (20.8) |
Junior College | 8,503 | (42.1) | 4,814 | (39.4) |
High School or Other | 5,604 | (27.8) | 4,838 | (39.6) |
Missing | 23 | (0.1) | 29 | (0.2) |
Residential Area, n (%) | ||||
Wards (Districts) | 5,964 | (29.5) | 3,409 | (27.9) |
Cities | 12,683 | (62.8) | 7,776 | (63.7) |
Towns or Villages | 1,544 | (7.7) | 1,031 | (8.4) |
