International casemix and funding models: lessons for rehabilitation

This series of articles for rehabilitation in practice aims to cover a knowledge element of the rehabilitation medicine curriculum. Nevertheless they are intended to be of interest to a multidisciplinary audience. The competency addressed in this article is 'An understanding of the different international models for funding of health care services and casemix systems, as exemplified by those in the US, Australia and the UK.'

Payment for treatment in healthcare systems around the world is increasingly based on fixed tariff models to drive up efficiency and contain costs. Casemix classifications, however, must account adequately for the resource implications of varying case complexity. Rehabilitation poses some particular challenges for casemix development.

The objectives of this educational narrative review are (a) to provide an overview of the development of casemix in rehabilitation, (b) to describe key characteristics of some well-established casemix and payment models in operation around the world and (c) to explore opportunities for future development arising from the lessons learned.

Diagnosis alone does not adequately describe cost variation in rehabilitation. Functional dependency is considered a better cost indicator, and casemix classifications for inpatient rehabilitation in the United States and Australia rely on the Functional Independence Measure (FIM). Fixed episode-based prospective payment systems are shown to contain costs, but at the expense of poorer functional outcomes. More sophisticated models incorporating a mixture of episode and weighted per diem rates may offer greater flexibility to optimize outcome, while still providing incentive for throughput.

The development of casemix in rehabilitation poses similar challenges for healthcare systems all around the world. Well-established casemix systems in the United States and Australia have afforded valuable lessons for other countries to learn from, but have not provided all the answers. A range of casemix and payment models is required to cater for different healthcare cultures, and casemix tools must capture all the key cost-determinants of treatment for patients with complex needs.