Different regional organisational models and the quality of health care: the case of coronary artery bypass graft surgery

Objectives: The Italian regions of Emilia-Romagna and Lombardy within the Italian National Health Service provide an opportunity to see if two different approaches to the organisation of care – one more hierarchical and planned, the other more competitive and market-like – influence its quality through examining the relationship between the number of coronary artery bypass grafts (CABGs) and the rate of in-hospital mortality using administrative data for the period 1996–1998. Methods: Descriptive statistics and logistic regression models were used. Results: The volume–outcome relation was statistically significant in both regions (odds ratio 0.71, P < 0.0001). Although CABG performance in Emilia-Romagna was slightly poorer than in Lombardy (OR 1.22, P < 0.05), the potential advantage in terms of the reduced risk of death for patients treated at high-volume versus low-volume hospitals was significantly greater. In Emilia-Romagna, the average performance advantage of high-volume units was more substantial in the case of private accredited hospitals than public hospitals (OR = 0.50, P < 0.0001 versus OR = 0.64, P < 0.0001). In Lombardy, the performance advantage of concentrating CABG procedures was greater in private research hospitals (OR = 0.67, P < 0.0001), whereas results were not statistically significant for the other types of hospital, indicating a good level of performance in both public and private hospitals even at low volumes. This also partially explained the lower mortality rate observed in that region. Conclusions: The degree of hierarchical regionalisation versus market-like arrangements characterising the two systems produced contrasting effects in terms of the quality of CABG surgery. Lombardy's more competitive environment appeared to achieve better performance in terms of a slightly lower probability of adverse outcomes, in a system with no formal assessment of population need and very high per capita revascularisation rates. To improve performance in the more hierarchical system adopted in Emilia-Romagna would require considerable effort to increase CABG surgery in low-volume cardiac units, and to sharpen performance incentives.