The case mix concept has been introduced in the U S A more than twenty years ago in order to measure hospital productivity and to promote quality of care.

The DRGs (Diagnosis Related Groups), developed by a team of researchers led by Robert Fetter and John Thompson at Yale University, were selected by HCFA (Health Care Financing Administration) in 1983 as the case mix classification system for the MEDICARE prospective payment system (PPS).

The DRG was the first “health management tool” to group patients in clinically meaningful categories with homogeneous resources consumption. All diagnostic categories and procedures based on medical record summaries could be coupled with financial data about resource uses, for individual patients, in order to differentiate high and low cost care.

Even if shortcomings were underlined since their beginning, DRGs are still used in the USA as the main tool for a case based, clinical encounter focused, payment.

What happened elsewhere? Many other countries have adopted the case mix concept after long periods of testing and accepting, but with large variations in data collection, information standards, grouping tools, financing methods and quality of care developments all over the world. Each country has developed a local clinical and political culture about case mix tools. The present book is intended to update the case mix situation, country by country. The available literature does not allow following the evolution in this specific area that modifies healthcare professionals' behaviour.

Some countries have gained experience in case mix for hospital financing, while others are only beginning to implement such system.

What are the objectives of their initiators? What results have they obtained? What difficulties have they encountered? What works and does not work? Can “DRG creep” be avoided? Would it be possible or not to obtain international comparisons, given the differences observed?

When preparing the joint Patient Classification system/Europe 2001 - EFMI (European Federation for Medical Informatics) working group 1 Conference to be held in Bruges on 10-14 October 2001, the editors felt that in the case mix area, there are “global views and local actions”. They decided to publish a book, in addition to the proceedings of the Conference on the present status of case mix in various countries in 2001.

Globalisation is not synonymous of universality. Globalisation implies that a single product could be sold to everyone. Universality, by contrast, is something more specific, with local empowerment taking in account cultural differences, where “global views” are shared all over the world but where local actions take into account local identity.

In the case mix area, like in many others, similar concepts have been endorsed in most countries, and global technologies are more and more used by everyone. However, health care delivery is influenced by each culture. This has a great impact on health care management, which has a strong local dimension.

Cultural clinical differences will lead to differentiation both in health care delivery, management and funding.

So health care delivery systems differ, but we need to learn from each other experiences. The book is an instrument to keep informed on the different local actions focused on implementing health management tools like case mix. We need to find a way to compare information about the health care delivered to patients by global case mix tools. A lot still has to be done to reach this universal objective. The PCS/E conferences and the EFMI Working Group 1 will maintain a global action to offer a platform for the local actors.

The increased rate of use of information systems by health care professionals will lead to improved basic patient data, which is the starting point for the development of good health management tools. Patient empowerment using information systems, requiring equity in health care, might be the driving force in future to modify present socio-cultural behaviours in using these tools.

Francis H. Roger France