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Table 2 Results from multivariate analysis

From: Multilevel competing risk models to evaluate the risk of nosocomial infection

Risk factors Event-specific analysis Subdistribution analysis
  Nosocomial bacteremia (NB) Death without NB in ICU Discharge without NB Nosocomial bacteremia
  HR (95% CI) HR (95% CI) HR (95% CI) Subdistribution HR (95% CI)
ICU / hospital-level covariates  
Number of beds in ICU:  
11–20 vs 0–10 1.18 (0.96–1.46) 1.01 (0.87–1.17) 1.43 (1.23–1.67) 1.34 (0.99–1.81)
21–30 vs 0–10 1.31 (0.97–1.77) 0.86 (0.69–1.08) 1.15 (0.89–1.47) 2.17 (1.42–3.30)
31–40 vs 0–10 1.56 (0.98–2.50) 0.81 (0.57–1.14) 1.83 (1.22–2.74) 1.85 (0.95–3.62)
> 40 vs 0–10 1.09 (0.55–2.18) 1.00 (0.60–1.65) 1.37 (0.76–2.48) 1.37 (0.50–3.72)
Number of beds in hospital:  
> 1000 vs 0–500 1.30 (0.85–1.99) 0.94 (0.70–1.27) 1.30 (0.90–1.87) 1.32 (0.71–2.47)
501–1000 vs 0–500 1.11 (0.91–1.36) 1.04 (0.90–1.21) 1.13 (0.95–1.34) 1.16 (0.87–1.53)
Teaching hospital (only) vs university+teaching 1.00 (0.82–1.22) 1.03 (0.89–1.20) 1.87 (1.61–2.18) 0.94 (0.71–1.26)
No teaching hospital vs university+teaching 0.71 (0.51–0.97) 1.08 (0.86–1.34) 2.42 (1.92–3.03) 0.59 (0.38–0.91)
Type of hospital (private vs public) 0.98 (0.70–1.39) 0.82 (0.64–1.05) 0.80 (0.61–1.05) 1.18 (0.76–1.85)
Type of ICU:  
Medical vs polyvalent 0.71 (0.44–1.14) 1.07 (0.78–1.47) 1.44 (0.99–2.10) 0.57 (0.30–1.08)
Surgery vs polyvalent 1.07 (0.62–1.85) 0.60 (0.40–0.91) 1.20 (0.73–1.96) 1.13 (0.51–2.50)
Coronary vs polyvalent 0.71 (0.28–1.82) 1.27 (0.64–2.51) 0.83 (0.44–1.57) 0.73 (0.24–2.28)
Traumatology vs polyvalent 1.20 (0.79–1.82) 1.03 (0.76–1.40) 1.28 (0.90–1.81) 1.15 (0.64–2.05)
Post-surgery cardiology vs polyvalent 1.47 (0.85–2.54) 0.71 (0.46–1.08) 1.95 (1.27–3.01) 1.39 (0.63–3.05)
Burn vs polyvalent 0.48 (0.16–1.42) 0.70 (0.31–1.62) 0.70 (0.31–1.59) 1.20 (0.30–4.79)
Calendar year of admission  
2007 vs 2006 1.02 (0.92–1.13) 1.01 (0.94–1.08) 0.95 (0.92–0.97) 1.02 (0.93–1.13)
2008 vs 2006 0.98 (0.89–1.08) 1.09 (1.02–1.16) 0.93 (0.91–0.95) 1.03 (0.93–1.14)
2009 vs 2006 1.09 (0.99–1.19) 1.02 (0.96–1.09) 0.86 (0.83–0.88) 1.19 (1.09–1.31)
2010+ vs 2006 0.84 (0.76–0.93) 1.08 (1.01–1.15) 0.94 (0.91–0.96) 0.83 (0.75–0.91)
Patient level covariates  
APACHE II score:  
11–20 vs 0–10 1.30 (1.20–1.42) 1.99 (1.85–2.14) 0.53 (0.52–0.54) 2.81 (2.59–3.06)
21–30 vs 0–10 1.38 (1.26–1.50) 4.11 (3.83–4.41) 0.28 (0.27–0.28) 4.54 (4.15–4.96)
> 31 vs 0–10 1.54 (1.37–1.73) 6.65 (6.15–7.19) 0.17 (0.17–0.18) 5.78 (5.14–6.49)
Age (years):  
0–40 vs 61–80 1.08 (0.99–1.18) 0.59 (0.55–0.64) 1.05 (1.03–1.07) 1.12 (1.02–1.22)
40–60 vs 61–80 1.09 (1.02–1.16) 0.79 (0.76–0.83) 0.98 (0.97–1.00) 1.18 (1.11–1.26)
> 80 vs 61–80 0.77 (0.68–0.86) 1.65 (1.57–1.73) 1.18 (1.15–1.21) 0.51 (0.45–0.57)
Days in hospital before ICU admission:  
4–6 vs 0–3 1.12 (1.00–1.25) 1.09 (1.01–1.17) 0.86 (0.83–0.89) 1.27 (1.13–1.42)
6–10 vs 0–3 1.14 (1.01–1.28) 1.18 (1.10–1.27) 0.85 (0.82–0.87) 1.33 (1.18–1.49)
> 10 vs 0–3 1.17 (1.08–1.27) 1.22 (1.16–1.29) 0.78 (0.76–0.80) 1.43 (1.32–1.55)
Type of diagnosis:  
Respiratory vs cardiovascular 0.86 (0.80–0.94) 0.93 (0.88–0.98) 0.63 (0.62–0.65) 1.43 (1.32–1.55)
Gastrointestinal vs cardiovascular 1.18 (1.09–1.29) 0.96 (0.91–1.02) 0.78 (0.76–0.79) 1.65 (1.51–1.80)
Central nervous system vs cardiovascular 0.91 (0.84–0.99) 1.41 (1.34–1.49) 0.65 (0.64–0.66) 1.38 (1.28–1.50)
Other diagnoses vs cardiovascular 1.20 (1.08–1.32) 0.78 (0.71–0.85) 0.76 (0.74–0.78) 1.96 (1.78–2.16)
Antibiotic treatment 48 h before and/or after ICU admission 0.83 (0.77–0.88) 1.08 (1.04–1.13) 0.70 (0.69–0.71) 1.01 (0.95–1.09)
Gender 1.08 (1.01–1.14) 1.01 (0.97–1.05) 0.99 (0.98–1.01) 1.12 (1.06–1.18)
Origin (hospital/ICU vs community) 1.05 (0.98–1.12) 0.98 (0.94–1.02) 1.00 (0.99–1.02) 1.09 (1.02–1.17)
Trauma 1.13 (1.04–1.24) 0.67 (0.62–0.72) 0.64 (0.62–0.66) 1.81 (1.66–1.98)
Variance of heterogeneity (without covariates) 0.26 (SE 0.038) 0.14 (SE 0.019) 0.15 (SE 0.017) 0.64 (SE 0.076)
Variance of heterogeneity (with ICU-level covariates only) 0.20 (SE 0.030) 0.12 (SE 0.015) 0.09 (SE 0.011) 0.47 (SE 0.061)
Variance of heterogeneity (with patient-level covariates only) 0.25 (SE 0.037) 0.12 (SE 0.016) 0.17 (SE 0.025) 0.56 (SE 0.069)
Variance of heterogeneity (with all covariates) 0.19 (SE 0.030) 0.11 (SE 0.015) 0.17 (SE 0.024) 0.40 (SE 0.052)
  1. CI, confidence interval; HR, hazard rate; NB, nosocomial bacteremia; SE, standard error.