[Considerations for standardization of assessment of performance capacity in rehabilitation medicine].

Specific difficulties in the assessment of reduced performance capacity in patients with gastroenterologic illness led to the development of a standardized and unified assessment method. The following five steps--exemplified for chronic liver-disease--were designed: (1) determination of disease features (and their graduations), leading to reduced performance capacity; (2) construction of a detailed performance capacity model using more concrete factors (e.g. motivation, cognition, cardiovascular-pulmonary system, etc.); (3) deduction of rules between disease features and the concrete factors of performance capacity, describing the expected (unfavourable) limitations; (4) consideration of individual limitations on the level of the concrete factors, and (5) conversion into a computer-aided expert system. The benefit of the method developed lies in prompt and practicable assistance by the expert system and in transparency of the decision processes. Therefore, performance capacity assessment will certainly gain in reliability and objectivity.