Characteristics | Univariable | Multivariable |
---|---|---|
 | OR (95% CI) | Adjusted OR (95% CI) |
Age group | Â | Â |
 20–29 | Reference | Reference |
 30–39 | 1.25 (1.13–1.38) | 1.25 (1.13–1.39) |
 40–49 | 1.42 (1.29–1.56) | 1.31 (1.19–1.45) |
 50–59 | 1.91 (1.75–2.09) | 1.60 (1.47–1.75) |
 60–69 | 2.91 (2.67–3.17) | 2.11 (1.93–2.31) |
 Over 70 | 6.22 (5.73–6.76) | 3.66 (3.36–3.99) |
Sex (male) | 1.36 (1.32–1.39) | 1.35 (1.32–1.39) |
Poverty (yes) | 1.45 (1.39–1.51) | 1.08 (1.04–1.13) |
Asthma (yes) | 2.83 (2.73–2.93) | 1.73 (1.66–1.80) |
COPD (yes) | 3.60 (3.44–3.77) | 1.62 (1.53–1.71) |
Other chronic lower respiratory disease (yes) | 2.56 (2.48–2.64) | 1.79 (1.73–1.85) |
CKD (yes) | 1.71 (1.62–1.81) | 1.07 (1.00–1.14)* |
Anemia (yes) | 1.42 (1.36–1.48) | 1.04 (1.00–1.10)†|
Tube feeding (yes) | 11.25 (10.82–11.71) | 3.32 (3.16–3.50) |
Suction (yes) | 7.15 (6.89–7.42) | 2.34 (2.23–2.47) |
Positioning (yes) | 4.71 (4.57–4.86) | 1.63 (1.55–1.72) |
Surgery (no) | 2.76 (2.67–2.85) | 2.98 (2.87–3.09) |
Mechanical ventilation (yes) | 11.40 (10.85–11.98) | 2.31 (2.15–2.47) |
ICU admission (yes) | 4.22 (4.09–4.35) | 1.29 (1.22–1.36) |
Location of hospital | Â | Â |
 Seoul metropolitan area | Reference | Reference |
 Other metropolitan area | 1.09 (1.05–1.14) | 1.16 (1.06–1.26) |
 Province | 1.40 (1.35–1.45) | 1.20 (1.11–1.31) |
Type of hospital | Â | Â |
 Tertiary | Reference | Reference |
 General | 1.53 (1.37–1.69) | 1.54 (1.39–1.70) |
Bed-to-nurse ratio‡ (n = 425,953) |  |  |
 Grade 1 | Reference | Reference |
 Grade 2 | 1.12 (1.03–1.23) | 1.16 (1.06–1.27) |
 Grade 3 | 1.36 (1.24–1.50) | 1.31 (1.19–1.44) |
 Grade 4 | 1.59 (1.42–1.78) | 1.42 (1.26–1.59) |
 Grade \(\ge\) 5 | 1.62 (1.49–1.77) | 1.45 (1.32–1.59) |
Type of hospital room (n = 504,279) |  |  |
 ≤ 3 beds | Reference | Reference |
 4 beds | 5.38 (4.83–5.99) | 3.26 (2.92–3.64) |
 5 beds | 6.08 (5.48–6.76) | 3.34 (3.00–3.72) |
 6 beds | 5.10 (4.60–5.65) | 3.08 (2.77–3.42) |
Ward with or without caregiver§ (n = 469,588) |  |  |
 With caregivers | 1.09 (1.03–1.14) | 1.19 (1.12–1.26) |
 Without caregivers | Reference | Reference |