Background Hierarchical modelling represents a statistical method used to analyze nested
data, as those concerning patients afferent to different hospitals. Aim of this paper is to build …

Objective: During the last decade, a worldwide growing interest in evaluating performance of
health services through 'outcome studies' took place. This study started in early 2002 and …

Background The availability of two contemporary sources of information about coronary
artery bypass graft (CABG) interventions, allowed 1) to verify the feasibility of performing …

Objectives: To compare the risk-adjustment model empirically derived from the 'Italian CABG
Outcome Project'with that of the additive and logistic EuroSCORE in terms of accuracy …

Objective To develop a risk stratification model to assess open heart surgery mortality in
Catalonia (Spain) in order to use risk-adjusted hospital mortality rates as an approach to …

Objective To compare the performance of several risk-scoring models to predict surgical
mortality following open heart surgery. Design A prospective observational study. Setting …

Background: In recent years, several studies in the medical and health service research
literature have advocated the use of hierarchical statistical models (multilevel models or …

Background—The calibration of several cardiac clinical prediction models has deteriorated
over time. We compare different model fitting approaches for in-hospital mortality after …

Conclusions There is a significant variation in patients risk profile and surgical strategy both
within Europe and across the Atlantic. Therefore, it is not appropriate to assess the quality of …

Objective: To construct models for predicting mortality, morbidity and length of intensive care
unit (ICU) stay after cardiac surgery and to compare the performance of these models with …