Dawwas et al have published an impressive paper (see page 1606),1 which compares 90-day mortality, mortality between 90 days and the first year, and long-term survival beyond the first year in patients after primary liver transplantation (LTx) performed in the United States (USA) with that performed in the United Kingdom (UK) and Ireland between 1994 and 2005. For their analysis they used the corresponding transplant databases, such as the Liver Transplant Audit and the Organ Procurement and Transplant Network/United Network for Organ Sharing (OPTN/UNOS), respectively. After careful modification, both databases were harmonised in order to perform an adequate statistical analysis.

The main finding of their analysis was that the 90-day mortality was significantly higher in UK/Ireland than in the USA, both in patients receiving a transplant for acute liver failure and in patients with chronic liver disease. In contrast, patients who survived the first years after LTx in the UK/Ireland had a lower overall risk-adjusted mortality than their counterparts in the USA. Based on these findings, the authors have concluded that the USA has better acute perioperative care than the UK/Ireland, whereas UK and Ireland seem to provide better quality long-term care after LTx.

Overall, the study itself was well planned and designed. The authors made sure that the data were harmonised as necessary, and only patients with a defined number of complete datasets were included. It is known that with such large databases there is a problem with data quality and transfer, but the overall quality of both transplantation databases is generally …