Table 1 Baseline characteristics for study population from the NIS

N (%)

25,945 (0.12)

21,374,337 (99.88)

Age (years)

31.00 ± 0.15

49.51 ± 0.01

< 0.001

Sex (%)

< 0.001

 Female

58.40

56.40

 Male

41.60

43.60

Race

< 0.001

 White

72.28

64.95

 Black

9.36

15.24

 Hispanic

12.03

12.53

 Asian or Pacific Islander

2.07

3.11

 Native American

0.57

0.66

 Other

3.70

3.52

Payer

< 0.001

 Medicare

24.64

40.42

 Medicaid

30.16

23.00

 Private insurance

39.18

29.45

 Self-pay

2.16

3.98

 No charge

0.11

0.31

 Other

3.74

2.85

Location

< 0.001

 “Central” counties of metro areas of > = 1 million population

28.35

30.07

 “Fringe” counties of metro areas of > = 1 million population

26.20

24.02

 Counties in metro areas of 250,000-999,999 population

21.86

20.73

 Counties in metro areas of 50,000-249,999 population

9.39

9.22

 Micropolitan counties

8.24

9.13

 Not metropolitan or micropolitan counties

5.97

6.83

Diagnoses per discharge (number)

< 0.001

 0

0.00

0.03

 1–5

18.57

25.90

 6–10

27.14

26.49

 11–15

23.72

20.77

 > 15

30.57

26.81

Procedures per discharge (number)

< 0.001

 0

33.20

38.86

 1–5

57.03

55.64

 6–10

7.30

4.56

 11–15

1.96

0.76

 > 15

0.51

0.18

Discharge disposition

< 0.001

 Routine

73.09

68.39

 Transfer to short-term hospital

 Transfer to other facility

2.50

1.97

 Home health care

10.04

14.00

 Against medical advice

11.75

12.37

 Died in hospital

0.87

1.31

 Discharged/transferred to court/law enforcement

1.73

1.94

 Discharged alive, destination unknown

0.02

0.02

Elective

< 0.001

 Elective admission

31.69

20.87

 Nonelective admission

68.31

79.13

Transfer in

< 0.001

 Not transferred in/newborn

87.63

91.04

 From acute care hospital

9.16

5.97

 From another type of health facility

3.22

3.00

Transfer out

< 0.001

 Not a transfer

87.46

84.03

 To acute care hospital

2.50

1.97

 To another type of health facility

10.04

14.00