ABSTRACT
I. INTRODUCTION Scientific evaluation of the outcome of therapeutic interventions in patients is not possible without assessment both before and after the intervention. The methods and measurements used must conform to set criteria so that they may be applied to all interventions and comparisons among studies may be made. They must be valid, accurate, precise, reliable, and repeatable using a test-retest variation. Evaluations should be properly directed, such that the right variable is measured. Even though methods of intervention and evaluation may vary, certain domains of measurement should be represented and a multidimensional approach undertaken. The time scale for evaluations and interventions and the composition of the study group are important factors so that some standardization exists, enabling understanding of the results by other investigators and comparison between studies.
