Outcome and resource use in critical care (electronic supplementary material)
Variability in outcome and resource use in intensive care units
Hans U. Rothen, Kay Stricker, Johanna Einfalt, Peter Bauer, Philip G.H. Metnitz,
Rui P. Moreno, Jukka Takala
Electronic supplementary material
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Outcome and resource use in critical care (electronic supplementary material)
Table 2E (electronic material): Key variables for structure and process
The total number of intensive care units included is 275; the total number of patients is 16,560.
Table 2E-a: Structure and staffing
mean ± SD
Number of staffed beds
median
(25th – 75th percentile)
10.94 ± 6.97
9.00
(7.00 - 12.00)
Physicians per bed
0.93 ± 0.77
0.81
(0.50 - 1.13)
Intensive care medicine specialists per bed
0.53 ± 0.67
0.37
(0.18 - 0.74)
11.53 ± 4.11
13.00
Nurses per bed
3.44 ± 2.75
3.00
(2.33 - 3.88)
Physicians per nurse
0.33 ± 0.30
0.28
(0.17 - 0.39)
Number of medical specialties in hospital
(10.00 - 15.00)
Data are mean ± SD and median (25th –75th percentile).
Table 2E-b: Hospital characteristics and clinical processes in the ICU
yes
no
yes
no
n
n
%
%
University hospital
122
141
46
54
Presence of emergency department in hospital
239
24
91
9
Multidisciplinary meetings in the ICU
121
136
47
53
Clinical rounds (physicians + nursing staff) in the ICU
158
99
61
39
Availability of physicians (weekdays) in the ICU
210
51
80
20
Availability of physicians (nights/weekends) in the ICU
204
57
78
22
Note: Due to missing data, the numbers do not sum up to n = 275.
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Outcome and resource use in critical care (electronic supplementary material)
Table 4E (electronic material): Estimated efficiency: Univariate logistic regression analysis of
explanatory variables. Stratification of groups by tertiles.
Variable
OR
95% CI
P
Number of staffed beds
1.05
0.97 – 1.13
0.231
Physicians per bed
0.36
0.15 – 0.88
0.026
Number of intensive care medicine specialists
0.95
0.84 – 1.06
0.362
Intensive care medicine specialists per bed
0.28
0.08 – 0.98
0.047
Number of medical specialties in hospital
1.01
0.92 – 1.11
0.852
Nurses per bed
2.02
1.30 – 3.15
0.002
Physicians per nurse
0.01
0.00 – 0.14
0.001
Type of hospital
1.13
0.46 – 2.78
0.783
Emergency department in hospital
7.16
0.59 – 86.62
0.122
Multidisciplinary meetings
1.24
0.49 – 3.17
0.648
Clinical rounds
4.07
1.54 – 10.75
0.005
Physicians (weekdays)
0.22
0.06 – 0.80
0.022
Physicians (nights/weekends)
0.34
0.10 – 1.23
0.101
1
1.94
0.11 – 34.92
0.655
2
0.02
0.00 – 0.12
<0.001
3
1.00
4
0.11
0.01 – 1.43
0.09
5
0.01
0.02 – 0.33
< 0.001
Region
Stratification of groups by tertiles. “Most efficient” units are units with both SMR and SRU in the lowest
tertile. These are compared to “least efficient” units (both SMR and SRU in the highest tertile). See
also figure 1 and table 2.
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Outcome and resource use in critical care (electronic supplementary material)
Type of hospital: Y = university hospital; N = non-university hospital
Emergency department (ED): Y = hospital has an ED; N = hospital has no ED.
Clinical rounds: Y = clinical rounds (physicians and nursing staff together) in the ICU; N = no common
clinical rounds in ICU.
Physicians (weekdays): Y = physicians are available in ICU on weekdays; N = physicians are not
available.
Physicians (nights/weekends): Y = physicians are available in ICU during the night and/or on
weekends; N = physicians are not available.
Region: see legend to table 3.
OR: Odds Ratio for being in the lowest SMR and lowest SRU tertile as compared to the highest SMR
and highest SRU tertile.
For region: OR is calculated as compared to region 3 (= reference group).
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Outcome and resource use in critical care (electronic supplementary material)
Table 5E (electronic material): Estimated efficiency: Multiple regression analysis of explanatory
variables. Stratification of groups by tertiles.
Variable
OR
Physicians per bed
na
Intensive care medicine specialists per bed
na
Nurses per bed
na
Physicians per nurse
na
Clinical rounds
na
Physicians (weekdays)
na
95% CI
P
Region
1
1.88
0.10 – 35.45
2
0.03
0.00 – 0.20
< 0.001
3
1.00
4
0.01
0.00 – 2.06
0.093
5
0.11
0.03 – 0.46
0.002
0.673
Stratification of groups by tertiles. “Most efficient” units are units with both SMR and SRU in the lowest
tertile. These are compared to “least efficient” units (both SMR and SRU in the highest tertile). See
also figure 1 and table 2.
Stepwise logistic regression analysis. Initially, all significant variables of univariate analysis are
entered into the model. For region, OR is calculated as compared to region 3 (= reference group)
R2 = 0.28 (Cox and Snell), R2 = 0.40 (Nagelkerke), area under the receiver operating
characteristics (ROC) curve = 0.72
na: variable did not enter the model.
For region: OR is calculated as compared to region 3 (= reference group).
For further legends see table 4.
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Outcome and resource use in critical care (electronic supplementary material)
SMR vs. geographical region
Figure 2E (electronic material): SMR and SRU vs. geographical region
3
2
SMR
1
0
ion
g
e
r
1
n3
io
reg
n4
io
reg
n5
io
reg
n2
io
reg
SRU vs. geographical region
SRU
10
1
n1
n3
n4
n5
n2
o
o
o
o
o
i
i
i
i
i
reg
reg
reg
reg
reg
Geographical regions (x-axis) are ordered according to median SRU.
Region: see legend to table 3
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Outcome and resource use in critical care (electronic supplementary material)
SMR vs. type of hospital, presence of emergency department,
and presence of clinical rounds
Figure 3E (electronic material): SMR and SRU vs. structural properties of the ICU
SMR
2
1
0
it
sp
iv
un
ers
it
al
o
yh
en
erg
cy
d
art
ep
nt
me
ic
c li n
n
rou
al
ds
em
SRU vs. type of hospital, presence of emergency department,
Top panel: SMR vs. type
hospital, presence
of rounds
emergency department, and presence of common
andofpresence
of clinical
clinical rounds (physicians and nurses). Yes = open boxes, no = striped boxes
SRU
10
1
t
rsi
ive
un
l
ita
sp
o
yh
cy
en
erg
d
art
ep
nt
me
ic
clin
s
nd
rou
l
a
em
Bottom panel: SRU vs. type of hospital, presence of emergency department, and presence of
common clinical rounds (physicians and nurses).
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