Are pre-hospital time and emergency-department disposition time useful process indicators for trauma care in Italy?

Background: It is recommended that process indicators (PI) for trauma-care be validated in the setting where they are applied for quality assurance (QA) and quality improvement (QI). In a pilot attempt at trauma QA and QI, we evaluated pre-hospital time (PT) and emergency department disposition time (EDt) as possible PIs in three Italian trauma-referral hospitals. Methods: We used registry data on all the 753 major (ISS > 15) trauma cases admitted to the participating hospitals between the 1 July 2004 and the 31 June 2005. The distribution of PT and EDt in the hospitals was investigated together with the performances of the hospitals. The performances were evaluated in terms of patient outcome with multivariate regression models. Outcome measures were trauma death, Euroqol 5-D (EQ5D), and Glasgow Outcome Score (GOS). The possible PIs were then evaluated as independent predictors of outcome. Results: In the hospital with the best outcome-measures (Hospital A) PT and EDt were also the shortest. The differences in PT and EDt were significant (p < 0.05) versus Hospital B and Hospital C, respectively. However, at the patient level, longer PT and EDt were not independently associated with bad outcome. Neither a threshold could be found that indicated higher risks of bad outcome. EDt > 120 min was paradoxically associated with lower mortality. Conclusion: Although PT and EDt were significantly shorter in the hospital with best outcome performances, we could not confirm at the patient level their expected independent association with outcome. More evidence is needed before these indicators can be validated as standard tools for system analysis in our setting.