ABSTRACT
The importance of good definitions goes beyond a single research study or article. Definitions are necessary at the beginning of any thinking process. The importance of the best possible definitions is even more obvious when research findings, evidence, and experience are evaluated, combined, and integrated in meta-analyses and systematic reviews. Definitions of any variable or observation in medicine should allow proper measurement, classification, decision-making, action, and evaluation. Definitions in the health sciences represent a heterogeneous ensemble, which is in need of semantic clarification, structure, and categorization. There are several desirable qualities and attributes of definitions in health sciences. In defining clinical phenomena, both inclusion and exclusion criteria are subjects of orismology. The focus of critical appraisal in medical literature is expanding well beyond the cause-effect-relationships in etiology and control of health phenomena and problems. The composite definition concept applies both at classical clinical entities and new domains, concepts or techniques as well.
