Length of stay(LOS) by adherence to American Thoracic Society (ATS) guidelines in patients stratified by ATS risk group and pneumonia severity index (PSI) score
| Adherent | Nonadherent | Δ (95% CI) | p-value | |||
| Subjects n | LOS days | Subjects n | LOS days | |||
| ATS risk group# | ||||||
| III | 494 | 6.7 | 77 | 9.5 | 2.8 (0.6–5.1) | 0.02 |
| IIIa | 222 | 7.1 | 45 | 9.2 | 2.1 (-0.5–4.8) | 0.11 |
| IIIb | 272 | 6.3 | 32 | 9.8 | 3.5 (-0.6–7.7) | 0.09 |
| IV | 37 | 20.4 | 34 | 12.5 | -7.9 (-13.7– -2.1) | 0.008 |
| IVa | 30 | 20.8 | 6 | 20.5 | -0.3 (-15–14.4) | 0.97 |
| IVb | 7 | 18.6 | 28 | 10.8 | -7.8 (-18–2.4) | 0.11 |
| PSI risk group¶ | ||||||
| I | 53 | 6.9 | 13 | 8.6 | 1.7 (-2.8–6.2) | 0.45 |
| II | 87 | 5.9 | 7 | 8.4 | 2.5 (-1.4–6.4) | 0.21 |
| III | 99 | 6.5 | 14 | 8.8 | 2.3 (-0.6–5.2) | 0.12 |
| IV | 202 | 7.9 | 46 | 10.9 | 3.1 (0.2–5.9) | 0.04 |
| V | 90 | 10.3 | 31 | 11.6 | 1.2 (-2.1–4.5) | 0.46 |
| Total | 531 | 7.6 | 111 | 10.4 | 2.8 (0.93–4.66) | 0.004 |
Δ: difference; CI: confidence interval. #: ANOVA for trend in ATS risk group versus LOS in days (p<0.001); ¶: ANOVA for trend in PSI risk group versus LOS in days (p<0.001).