From: Multiple time scales in modeling the incidence of infections acquired in intensive care units
Risk factors | MODEL 1a basic time scale: ICU time | MODEL 2a basic time scale: calendar time | ||||
---|---|---|---|---|---|---|
 | MRSA | Death without MRSA | Discharge without MRSA | MRSA | Death without MRSA | Discharge without MRSA |
Patient level covariates | Â | Â | Â | Â | Â | Â |
APACHE II score 11–20 vs. 0–10 | 1.36 (1.01–1.83) | 2.05 (1.90–2.21) | 0.62 (0.61–0.63) | 1.40 (1.02–1.93) | 2.14 (1.97 2.32) | 0.64 (0.63–0.65) |
APACHE II score 21–30 vs. 0–10 | 1.52 (1.11–2.09) | 4.22 (3.90–4.56) | 0.37 (0.36–0.38) | 1.53 (1.08–2.17) | 4.58 (4.22 4.97) | 0.38 (0.37–0.39) |
APACHE II score>31 vs. 0–10 | 1.52 (1.00–2.32) | 6.83 (6.28–7.44) | 0.25 (0.23–0.26) | 1.86 (1.18–2.96) | 7.73 (7.05 8.45) | 0.25 (0.24–0.26) |
Age (years) 0-40 vs. 61–80 | 1.07 (0.80–1.44) | 0.62 (0.57–0.67) | 1.08 (1.05–1.10) | 0.97 (0.71–1.34) | 0.62 (0.57 0.67) | 1.05 (1.02–1.08) |
Age (years) 40-60 vs. 61–80 | 0.97 (0.78–1.21) | 0.81 (0.77–0.85) | 1.00 (1.00–1.01) | 0.93 (0.74–1.18) | 0.81 (0.77 0.85) | 0.99 (0.97–1.01) |
Age (years)>80 vs. 61–80 | 0.73 (0.47–1.11) | 1.60 (1.52–1.70) | 1.12 (1.09–1.15) | 0.71 (0.45–1.11) | 1.63 (1.53 1.74) | 1.13 (1.10–1.16) |
Days in hospital before ICU admission: | Â | Â | Â | Â | Â | Â |
4-6 vs. 0–3 | 1.15 (0.79–1.68) | 1.11 (1.03–1.20) | 0.89 (0.86–0.92) | 1.30 (0.86–1.97) | 1.12 (1.03 1.22) | 0.92 (0.89–0.96) |
6-10 vs. 0–3 | 1.16 (0.78–1.73) | 1.22 (1.13–1.32) | 0.89 (0.86–0.92) | 1.00 (0.64–1.56) | 1.22 (1.12 1.33) | 0.91 (0.88–0.95) |
> 10 vs. 0–3 | 1.10 (0.82–1.48) | 1.24 (1.17–1.31) | 0.84 (0.81–0.86) | 1.21 (0.88–1.66) | 1.23 (1.16 1.32) | 0.86 (0.83–0.88) |
Type of diagnosis: | Â | Â | Â | Â | Â | Â |
Respiratory vs. cardiovascular | 1.13 (0.86–1.49) | 0.97 (0.92–1.02) | 0.76 (0.74–0.77) | 1.30 (0.96–1.75) | 0.97 (0.92 1.03) | 0.77 (0.75–0.79) |
Gastrointestinal vs. cardiovascular | 1.28 (0.95–1.73) | 1.01 (0.95–1.07) | 0.84 (0.82–0.86) | 1.39 (1.00–1.94) | 1.01 (0.94 1.08) | 0.84 (0.82–0.86) |
Central nervous system vs. cardiovascular | 1.18 (0.40–1.55) | 1.37 (1.30–1.45) | 0.77 (0.75–0.78) | 1.32 (0.98–1.77) | 1.39 (1.30 1.47) | 0.77 (0.75–0.79) |
Other diagnoses vs. cardiovascular | 0.90 (0.60–1.33) | 0.84 (0.76–0.92) | 0.86 (0.84–0.89) | 0.93 (0.56–1.54) | 0.84 (0.76 0.94) | 1.01 (0.98–1.05) |
Antibiotic treatment 48 h before and/or after ICU admission | 1.12 (0.89–1.40) | 1.10 (1.05–1.15) | 0.76 (0.75–0.78) | 1.29 (0.99–1.67) | 1.11 (1.06 1.17) | 0.72 (0.71–0.74) |
Gender | 1.14 (0.94–1.40) | 1.01 (0.97–1.05) | 1.00 (1.00–1.01) | 1.22 (0.98–1.52) | 1.00 (0.96 1.04) | 0.99 (0.97–1.00) |
Origin (hospital/ICU vs. community) | 0.94 (0.75–1.17) | 0.95 (0.91–1.00) | 1.03 (1.01–1.05) | 0.95 (0.74–1.21) | 0.96 (0.91 1.01) | 1.02 (1.00–1.04) |
Trauma | 1.20 (0.40–1.61) | 0.67 (0.62–0.73) | 0.74 (0.72–0.76) | 1.29 (0.94–1.78) | 0.66 (0.60 0.72) | 0.74 (0.71–0.76) |
Second time scale | Â | Â | Â | Â | Â | Â |
Calendar year of admission | Â | Â | Â | Â | Â | Â |
2007 vs. 2006 | 0.68 (0.51–0.92) | 1.05 (0.98–1.13) | 0.95 (0.93–0.98) |  |  |  |
2008 vs. 2006 | 0.57 (0.43–0.78) | 1.11 (1.04–1.20) | 0.92 (0.90–0.94) |  |  |  |
2009 vs. 2006 | 0.59 (0.44–0.79) | 1.11 (1.03–1.19) | 0.88 (0.86–0.91) |  |  |  |
2010+ vs. 2006 | 0.49 (0.36–0.67) | 1.15 (1.07–1.24) | 0.94 (0.91–0.96) |  |  |  |
Length of stay | Â | Â | Â | Â | Â | Â |
5-9 vs. 0–4 days |  |  |  | 4.63 (3.30–6.48) | 1.35 (1.28 1.42) | 1.47 (1.44–1.50) |
10-14 vs. 0–4 days |  |  |  | 4.66 (3.18–6.84) | 1.29 (1.20 1.38) | 0.85 (0.82–0.87) |
>14 vs. 0–4 days |  |  |  | 5.42 (3.87–7.57) | 1.05 (0.99 1.11) | 0.61 (0.59–0.63) |