Table 4 Factors determining hospital length of stay – regression results, Incidence Rate Ratios (IRRs)

Main diagnosis

 Schizophrenia (F20)

 Schizotypal disorder (F21)

0.91

(0.88; 0.94)

 Persistent delusional disorder (F22)

0.64

(0.62; 0.66)

0.96

(0.84; 1.08)

 Acute and transient psychotic disorder (F23)

0.77

(0.62; 0.95)

0.69

(0.61; 0.78)

 Induced delusional disorder (F24)

1.02

(0.99; 1.04)

0.82

(0.63; 1.05)

 Schizoaffective disorders (F25)

0.77

(0.69; 0.85)

1.09

(0.96; 1.23)

 Other nonorganic psychotic disorders (F28)

0.77

(0.74; 0.81)

0.82

(0.68; 0.98)

 Unspecified nonorganic psychosis (F29)

0.87

(0.85; 0.88)

0.82

(0.72; 0.94)

 Manic episode (F30)

0.93

(0.82; 1.06)

 Bipolar affective disorder (F31)

0.75

(0.72; 0.78)

1.14

(1.10; 1.18)

Patient demographics and clinical characteristics

 Age 25-34

0.99

(0.93; 1.04)

1.00

(0.91; 1.10)

1.01

(0.93; 1.10)

0.96

(0.89; 1.03)

 Age 35-44

0.94

(0.90; 0.99)

0.95

(0.88; 1.03)

0.94

(0.86; 1.02)

0.95

(0.88; 1.02)

 Age 45-54

0.99

(0.94; 1.03)

0.98

(0.91; 1.07)

0.98

(0.91; 1.05)

1.00

(0.93; 1.08)

 Age 55-64

1.10

(1.05; 1.16)

1.06

(0.97; 1.15)

1.17

(1.07; 1.27)

1.12

(1.04; 1.21)

 Age 65-74

1.32

(1.25; 1.39)

1.23

(1.12; 1.34)

1.40

(1.30; 1.52)

1.37

(1.26; 1.48)

 Age 75 and over

1.50

(1.41; 1.60)

1.34

(1.22; 1.48)

1.63

(1.47; 1.81)

1.56

(1.41; 1.72)

 Male

1.06

(1.00; 1.12)

1.04

(0.95; 1.13)

1.05

(0.96; 1.16)

1.06

(0.99; 1.14)

 Detained

1.41

(1.35; 1.47)

1.52

(1.45; 1.60)

1.35

(1.28; 1.42)

1.31

(1.25; 1.37)

 Ethnicity: mixed

1.07

(1.01; 1.13)

1.05

(0.97; 1.14)

1.09

(0.99; 1.19)

1.10

(0.99; 1.23)

 Ethnicity: Asian

1.03

(0.99; 1.06)

1.04

(0.99; 1.09)

1.04

(0.97; 1.12)

1.01

(0.97; 1.05)

 Ethnicity: black

1.12

(1.09; 1.15)

1.15

(1.10; 1.20)

1.11

(1.05; 1.17)

1.11

(1.04; 1.17)

 Ethnicity: unknown or missing

0.99

(0.95; 1.03)

1.03

(0.96; 1.09)

0.97

(0.91; 1.04)

0.95

(0.88; 1.02)

 Interaction: Detained + Ethnicity: mixed

0.94

(0.84; 1.06)

0.85

(0.74; 0.98)

0.98

(0.80; 1.20)

1.14

(0.92; 1.41)

 Interaction: Detained + Ethnicity: Asian

0.95

(0.89; 1.02)

0.91

(0.83; 1.00)

1.00

(0.91; 1.11)

0.93

(0.83; 1.05)

 Interaction: Detained + Ethnicity: black

0.93

(0.88; 0.98)

0.90

(0.85; 0.96)

0.91

(0.84; 0.99)

0.91

(0.84; 0.98)

 Interaction: Detained + Ethnicity: unknown or missing

0.99

(0.92; 1.06)

0.91

(0.82; 1.01)

1.03

(0.92; 1.16)

1.05

(0.90; 1.22)

 Patient has a carer

1.07

(1.02; 1.12)

1.07

(1.01; 1.13)

1.03

(0.96; 1.10)

1.10

(1.03; 1.17)

 Patient was previously treated for mental health issues

0.98

(0.94; 1.01)

0.95

(0.91; 0.99)

1.00

(0.96; 1.04)

1.01

(0.97; 1.05)

 MH benefit claimants - 2nd quintile

1.01

(1.00; 1.03)

1.00

(0.97; 1.03)

1.03

(0.99; 1.07)

1.02

(1.00; 1.05)

 MH benefit claimants - 3rd quintile

1.03

(1.01; 1.06)

1.01

(0.98; 1.04)

1.03

(0.99; 1.07)

1.06

(1.02; 1.09)

 MH benefit claimants - 4th quintile

1.06

(1.02; 1.09)

1.03

(0.99; 1.08)

1.04

(0.99; 1.09)

1.11

(1.07; 1.14)

 MH benefit claimants - 5th quintile

1.06

(1.03; 1.09)

1.03

(0.99; 1.07)

1.07

(1.01; 1.13)

1.11

(1.07; 1.15)

 Number of comorbidities

1.03

(1.01; 1.04)

1.02

(1.01; 1.04)

1.03

(1.01; 1.04)

1.03

(1.01; 1.05)

 Alcohol and substance misuse

0.90

(0.88; 0.93)

0.89

(0.85; 0.93)

0.95

(0.89; 1.01)

0.91

(0.86; 0.96)

 Co-morbid personality disorder

0.82

(0.77; 0.88)

0.80

(0.71; 0.90)

0.84

(0.73; 0.97)

0.84

(0.77; 0.91)

Discharge

 Self-discharged

0.55

(0.49; 0.62)

0.57

(0.50; 0.66)

0.56

(0.48; 0.66)

0.50

(0.44; 0.57)

 Died in hospital

0.93

(0.86; 1.00)

0.92

(0.81; 1.05)

0.98

(0.82; 1.17)

0.90

(0.80; 1.01)

Access to care

 Urban

1.01

(0.98; 1.04)

1.00

(0.96; 1.04)

1.01

(0.97; 1.06)

1.02

(0.99; 1.06)

 % residents of local community in psychiatric establishment

1.00

(0.98; 1.02)

1.00

(0.98; 1.03)

1.00

(0.95; 1.06)

0.99

(0.96; 1.02)

 Ability to access GP within 48 h

0.99

(0.94; 1.04)

1.00

(0.93; 1.08)

0.94

(0.83; 1.06)

1.00

(0.91; 1.10)

 Care plan developed in primary care

0.98

(0.94; 1.02)

0.95

(0.89; 1.02)

1.07

(0.98; 1.16)

0.97

(0.90; 1.05)

Time effects

 Year 2007

0.97

(0.93; 1.02)

0.97

(0.92; 1.02)

0.97

(0.92; 1.03)

0.97

(0.93; 1.02)

 Year 2008

1.00

(0.97; 1.04)

1.01

(0.97; 1.06)

0.99

(0.94; 1.04)

1.01

(0.96; 1.05)

 Year 2009

0.97

(0.92; 1.01)

0.97

(0.92; 1.03)

0.95

(0.91; 1.00)

0.97

(0.93; 1.01)

 Year 2010

0.93

(0.88; 0.98)

0.92

(0.86; 0.99)

0.92

(0.87; 0.98)

0.95

(0.89; 1.01)

Pseudo-R²

N