Table 5. Univariable Logistic Regression.

Univariable Analysis (N=441)^†

Predictor variable	Odds Ratio (95% CL)	P-value
Demographics
Age – (tertiles)
<40	Reference	--
50–59	7.65 (2.30–25.45)	<0.001
≥60	6.73 (1.92–23.52)	<0.01
Sex (M:F)	1.36 (0.78–2.39)	0.28
Race (AA:C)	0.81 (0.30–2.21)	0.51
Medical History
Asthma (Y/N)	0.33 (0.13–0.86)	0.02
Stroke (Y/N)	5.10 (2.39–10.91)	<0.0001
Cancer (Y/N)	1.31 (0.56–3.11)	0.53
HIV (Y/N)	0.96 (0.41–2.23)	0.92
Diabetes (Y/N)	1.44 (0.75–2.77)	0.28
EMS Characteristics
Nursing home transport (Y/N)	8.87 (4.30–18.29)	<0.0001
EMD chief complaint
DIB (Y/N)	0.70 (0.37–1.31)	0.26
Diabetes (Y/N)	0.90 (0.20–4.02)	0.88
Sick person (Y/N)	3.32 (1.84–6.01)	<0.0001
Altered or LOC (Y/N)	0.96 (0.32–2.85)	0.94
Initial EMS impression
Shock, RF or arrest (Y/N)	7.17 (1.74–29.53)	0.006
DIB (Y/N)	1.37 (0.70–2.69)	0.35
Diabetes (Y/N)	0.70 (0.16–3.08)	0.64
Altered or LOC (Y/N)	2.91 (1.49–5.68)	0.002
Fever, cough, infection (Y/N)	2.30 (0.87–4.62)	0.11
EMS Vital Signs
Hot tactile temp (Y/N)	3.81 (2.02–7.18)	<0.0001
SBP – per 1 mmHg increase	0.95 (0.93–0.97)	<0.0001
HR - per 1 bpm increase	1.01 (1.00–1.03)	0.02
RR – per 1 bpm increase	1.04 (1.00–1.08)	0.046
Oxygen saturation – per 1 % inc.	0.94 (0.91–0.97)	<0.0001
Blood glucose – per 1 mg/dL inc.	1.00 (1.00–1.00)	0.12
GCS – per 1 point increase (3–15)	0.86 (0.80–0.92)	<0.0001

Definitions: HIV – human immunodeficiency virus; DIB – difficulty in breathing; EMD – Emergency Medical Dispatch; RF – respiratory failure; LOC – loss of consciousness; SBP – systolic blood pressure; HR – heart rate; RR – respiratory rate; GCS – Glascow Coma Scale; CL – confidence limit.

^†Analysis performed in the derivation subgroup.

^*All variables modeled as binary categorical predictors (1-present; 0-absent) unless otherwise stated. Sex modeled as male vs. female (reference); race modeled African-American vs. Caucasian (reference). Age, SBP, heart rate, respiratory rate, oxygen saturation, GCS and blood glucose modeled as continuous variables.