k of death sellckchem in accepted versus non-accepted patients, expressed in terms of odds ratio, was 0.7 (95% CI: 0.5 to 0.9; P = 0.017). The odds ratio increasingly favoured intensive care admission as predicted mortality rose. In patients with >40% predicted mortality the odds ratio reached 0.6 (95% CI: 0.4 to 0.8; P = 0.004).Table 3Results of the mortality analysisCostsTotal cost per hospital stay for patients accepted and not accepted into ICU are reported in Table Table2.2. The mean daily cost per patient was $371 (�294) (95% CI: $368 (�292) to $374 (�296)) for the ward stay and $1,339 (�1,063) (95% CI: $1,334 (�1,059) to $1,343 (�1,066)) for the ICU stay.After adjusting the analyses of costs for the same variables, the estimated difference in costs per patient between accepted and not accepted was $6,156 (�4,886) (95% CI: $5,028 (�3,990) to $7,283 (�5,780)).

Cost effectiveness of ICU admissionBased on the results of the adjusted analyses of 28-day mortality and costs, the estimate of cost per life saved was $103,771 (�82,358) (95% CI: $56,855 (�45,123) to $150,687 (�119,593)). The values of life expectancy assigned to each patient gave an average life expectancy in our population of 14.7 years after hospital discharge. Using this average figure, a cost per life-year saved of $7,065 (�5,607) (95% CI: $3,871 (�3,072) to $10,259 (�8,142)) was obtained. The cost effectiveness of ICU admission increased with increasing predicted mortality (Table (Table44).

Table 4Results of the cost-effectiveness analysisEstimates of cost per life saved and cost per life-year saved were similar when considering mortality at three months, $103,418 (�82,078) (95% CI: $44,198 (�35,078) to $162,639 (�129,079)) and $7,041 (�5,588) (95% CI: $3,009 (�2,388) to $11,073 (�8,788)), respectively.Sensitivity analysesExcluding centres with extreme resultsIn this sensitivity analysis we excluded 1,471 patients (19.7% of the whole sample) from two centres, which showed the most extreme positive and negative mortality results. Results of the analysis for 28-day mortality were a cost per life saved of $119,301 (�94,683) ($26,581 (�21,096) to $212,020 (�168,270)) and a cost per life-year saved of $8,121(�6,445) ($1,810 (�1,437) to $14,432 (�11,454)).Excluding problematic categories of patientsWhen excluding patients referred to ICU for observation (n = 2,363; 32% of the whole sample), 13.

9% of the patients were refused admission. The results for the effect of ICU admission on mortality at 28 days (0.7; 95% CI: 0.5 to 0.9; P = 0.020) were the same as those in the main analysis, while the difference in costs between admitted and non-admitted patients Brefeldin_A was higher at $10,409 (�8,261) ($8,479 (�6,729) to $12,340 (�9,794); P < 0.001). As a consequence, this sensitivity analysis suggests a lower cost effectiveness of ICU admission compared with the main analysis, although the estimates of the two cost-effectiveness measures became less accurate due to the loss of nearly one third of the sample size