Table 2 Multivariable model of in-patient admission with risk score using derivation set Akiake Information Criterion (intercept only 2326760, intercept and covariates 1768771) Area under Receiver Operator curve for validation dataset 0.82 (95% CI 0.81, 0.82). Hosmer-Lemeshow test statistic p < 0.001

Age

16–19 yrs

Ref

Na

0

20–39 yrs

0.19

1.21 (1.19,1.23)

<0.001

+1

40–59 yrs

0.61

1.85 (1.82, 1.88)

<0.001

+3

60–79 yrs

1.20

3.31 (3.25, 3.37)

<0.001

+6

≥80 yrs

1.79

6.01 (5.89, 6.13)

<0.001

+9

Ambulance arrival

0.77

2.17 (2.15, 2.19)

<0.001

+4

Triage category

1

4.47

87.13 (82.15, 92.60)

<0.001

+24

2

2.99

19.84 (19.28, 20.32)

<0.001

+16

3

2.08

7.97 (7.80, 8.15)

<0.001

+11

4

1.10

3.00 (2.94, 3.07)

<0.001

+5

5

Ref

Na

0

Admission within 30 days

0.66

1.93 (1.90, 1.96)

<0.001

+3

ED arrival time

0800–1759

0.21

1.23 (1.22, 1.25)

<0.001

+1

1800–2259

0.01

1.01 (1.00, 1.02)

0.06

0

2300–0759

Ref

na

0

Presenting problem

Abdominal, gastrointestinal

0.33

1.39 (1.37, 1.41)

<0.001

+2

Cardiovascular

−0.71

0.49 (0.46, 0.48)

<0.001

−3

General symptoms

Ref

Na

0

Febrile illness

0.65

1.91 (1.87, 1.96)

<0.001

+3

Injury

−0.75

0.47 (0.46, 0.49)

<0.001

−4

Respiratory

0.01

1.01 (0.99,1.03)

0.19

0

Musculoskeletal

−0.57

0.56 (0.55, 0.57)

<0.001

−3

Neurological

−0.25

0.78 (0.77, 0.79)

<0.001

−1

Mental health

−0.32

0.72 (0.71, 0.74)

<0.001

−2

Toxicological

−0.30

0.74 (0.72, 0.77)

<0.001

−2

ENT/eye/head and neck

−1.17

0.31 (0.30, 0.32)

<0.001

−6

Administrative

−0.57

0.57 (0.55, 0.59)

<0.001

−3

Genitourinary

−0.16

0.85 (0.83, 0.87)

<0.001

−1

Social

0.19

1.21 (1.07, 1.38)

0.004

+1

Endocrine

−0.03

0.97 (0.91, 1.05)

0.26

0

Obstetrics, Gynaecology

−0.55

0.58 (0.56, 0.59)

<0.001

−3

Skin, allergy

−0.30

0.74 (0.72, 0.76)

<0.001

−2

Other medical

0.99

2.70 (2.40, 3.04)

<0.001

+5