The National Health Service Blood and Transplant Cardiothoracic Advisory Group, in line with the principles of priority to the sickest and equal access to opportunities to benefit from transplantation, revised the UK Lung Allocation Scheme (UKLAS) from a geography-based to a clinical urgency-based scheme. The primary aim was to prioritise the sickest registered lung transplant candidates, providing access to the national donor lung pool, irrespective of geographical zones. Two criteria-based urgent tiers were adopted in the 2017 UKLAS: (1) the super-urgent lung allocation scheme (SULAS) for patients on extracorporeal membrane oxygenation support and (2) the urgent lung allocation scheme (ULAS) for patients with deterioration in disease-specific physiological parameters.

In the current issue of Thorax, Al-Adhami and colleagues reported on the impact of this change in the UKLAS, declaring that ‘…it has successfully delivered on its remit by reducing overall median waiting-times by 135 days and increasing the odds of transplantation at 6 months by 41%’.1 These are undoubtedly laudable results; and it is easy to conclude that the change in UKLAS has been a success, but there is more to these headline results. Before further scrutiny of these data, a comparison with other lung allocation systems may provide the relevant context.

In May 2005, the Organ Procurement and Transplantation Network and United Network for Organ Sharing introduced the first major change to lung allocation by implementing the lung allocation score (LAS) as the primary determinant for lung allocation (instead of waiting time) in the USA. The principal goal was to reduce the number …