Table 5 Incidence of TBI across birth order categories, 1987–2005.

From: Birth order and pediatric traumatic brain injury

Birth order

D

Y

I = D/Y

SE

LCI

UCI

First time diagnosed TBI 1987–1992

First

82

128,629.58

63.748

7.039

49.95

77.55

Second

104

116,656.26

89.150

8.741

72.01

106.3

Third

47

53,306.18

88.169

12.860

62.96

113.4

Fourth or higher

31

88.169

120.205

21.589

77.89

162.5

First time diagnosed TBI 1993–1998

First

172

267,887.3

64.206

4.895

54.61

73.8

Second

168

243,048.96

69.121

5.332

58.66

79.57

Third

77

111,160.12

69.269

7.893

53.79

84.74

Fourth or higher

47

53,838.44

87.298

12.733

62.34

112.3

First time diagnosed TBI 1999–2005

First

359

428,999.55

83.683

4.416

75.02

92.43

Second

294

389,640.84

75.454

4.400

66.82

84.08

Third

154

176,741.52

86.415

6.963

72.76

100.1

Fourth or higher

79

85,391.9

91.527

10.297

71.34

111.7

First time diagnosed TBI 1987–2005

First

613

426,154.12

143.844

5.809

132.4

155.2

Second

566

386,427.58

146.469

6.156

134.4

158.5

Third

278

176,741.52

157.291

9.433

138.8

175.8

Fourth or higher

157

85,391.9

183.858

14.673

155.0

212.6

  1. I = incidence, D = TBI cases, Y = person-years = time from birth until TBI, death, emigration or end of the follow-up, LCI = lower bound of confidence interval(95%CI), UCI = upper bound of confidence interval (95%CI).