J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website http://www.jocmr.org

Original Article

Volume 9, Number 11, November 2017, pages 911-916

Overcrowding and Its Association With Patient Outcomes in a Median-Low Volume Emergency Department

Figure 1. Boxplot of median total length of stay in patients under different levels of crowding measured by different crowding tools. The red line indicates the median length of stay (150 min) among all ED patients. 0: not busy; 1: busy; 2: extremely busy; 3: overcrowded.

**Table 1.** Emergency Department Study Patient General Information
n: number; IQR: interquartile range; ESI: emergency severity index; LWBS: left without being seen/eloped.
Total number of patients registered at study ED (n)	2,987
Number of patients for data analysis (n)	2,557
Male (n, %)	1,066 (42%)
Age (years) (median, IQR)	42 (25 - 63)
Acuity level (n, %)
ESI 1	13 (0.51%)
ESI 2	290 (11.34%)
ESI 3	1,566 (61.24%)
ESI 4	609 (23.82%)
ESI 5	52 (2.03%)
Unclassified	27 (1.06%)
Admissions (n, %)	267 (10.63%)
Length of stay (minutes) (median, IQR)	150 (99 - 213)
Patients eloped/LWBS (n, %)	8 (0.3%)

Table 1. Emergency Department Study Patient General Information

n: number; IQR: interquartile range; ESI: emergency severity index; LWBS: left without being seen/eloped.

Total number of patients registered at study ED (n)

2,987

Number of patients for data analysis (n)

2,557

Male (n, %)

1,066 (42%)

Age (years) (median, IQR)

42 (25 - 63)

Acuity level (n, %)

ESI 1

13 (0.51%)

ESI 2

290 (11.34%)

ESI 3

1,566 (61.24%)

ESI 4

609 (23.82%)

ESI 5

52 (2.03%)

Unclassified

27 (1.06%)

Admissions (n, %)

267 (10.63%)

Length of stay (minutes) (median, IQR)

150 (99 - 213)

Patients eloped/LWBS (n, %)

8 (0.3%)

**Table 2.** Median Length of Stay in Minutes Across Levels of Crowding Measured by Different ED Crowding Tools
	NEDOCS	CEDOCS	SONET
NEDOCS: National Emergency Department Overcrowding Score; CEDOCS: Community Emergency Department Overcrowding Score; SONET: Severely-overcrowding Overcrowding, and Not-Overcrowding Estimation Tool; LOS: length of stay; IQR: interquartile range.
Not busy	880	34.4	132.6	88.0 - 200.9	44	1.7	117.0	62.5 - 179.4	40	1.6	117.0	61.4 - 179.4
Busy	1,106	43.3	150.6	98.6 - 207.8	2,206	86.3	146.0	96.3 - 209.0	1,730	67.7	142.4	93.3 - 204.8
Extremely busy	514	20.1	171.9	118.1 - 237.8	307	12.0	185.6	124.9 - 252.0	733	28.7	166.8	112.7 - 231.2
Overcrowded	57	2.2	203.3	155.7 - 254.5					54	2.1	193.3	143.4 - 254.5

Table 2. Median Length of Stay in Minutes Across Levels of Crowding Measured by Different ED Crowding Tools

NEDOCS

CEDOCS

SONET

Median LOS

IQR

Median LOS

IQR

Median LOS

IQR

NEDOCS: National Emergency Department Overcrowding Score; CEDOCS: Community Emergency Department Overcrowding Score; SONET: Severely-overcrowding Overcrowding, and Not-Overcrowding Estimation Tool; LOS: length of stay; IQR: interquartile range.

Not busy

880

34.4

132.6

88.0 - 200.9

1.7

117.0

62.5 - 179.4

1.6

117.0

61.4 - 179.4

Busy

1,106

43.3

150.6

98.6 - 207.8

2,206

86.3

146.0

96.3 - 209.0

1,730

67.7

142.4

93.3 - 204.8

Extremely busy

514

20.1

171.9

118.1 - 237.8

307

12.0

185.6

124.9 - 252.0

733

28.7

166.8

112.7 - 231.2

Overcrowded

2.2

203.3

155.7 - 254.5

2.1

193.3

143.4 - 254.5

**Table 3.** Time Ratios for Median Length of Stay Across Levels of Crowding Measured by Different ED Crowding Tools
	NEDOCS	CEDOCS	SONET
NEDOCS: National Emergency Department Overcrowding Score; CEDOCS: Community Emergency Department Overcrowding Score; SONET: Severely-overcrowding Overcrowding, and Not-Overcrowding Estimation Tool; TR: time ratio; CI: confidence interval; REF: reference.
Not busy	REF	REF	REF	REF	REF	REF
Busy	1.09	1.04 - 1.15	1.25	1.01 - 1.55	1.26	0.99 - 1.61
Extremely busy	1.27	1.19 - 1.35	1.56	1.25 - 1.95	1.47	1.15 - 1.87
Overcrowded	1.48	1.32 - 1.67	-	-	1.72	1.31 - 2.25

Table 3. Time Ratios for Median Length of Stay Across Levels of Crowding Measured by Different ED Crowding Tools

NEDOCS

CEDOCS

SONET

95% CI

Not busy

REF

Busy

1.09

1.04 - 1.15

1.25

1.01 - 1.55

1.26

0.99 - 1.61

Extremely busy

1.27

1.19 - 1.35

1.56

1.25 - 1.95

1.47

1.15 - 1.87

Overcrowded

1.48

1.32 - 1.67

1.72

1.31 - 2.25