Abstract
Sir Ronald Fisher used a single-subject design to derive the concepts of appropriate research design, randomization, sensitivity, and tests of statistical significance. The seminal work of Broca demonstrated that valid and generalizable findings can and have emerged from studies of a single patient in neuropsychology. In order to assess the reliability and/or validity of any clinical phenomena that derive from single subject research, it becomes necessary to apply appropriate biostatistical methodology. The authors develop just such an approach and apply it successfully to the evaluation of the functioning, quality of life, and neuropsychological symptomatology of a single schizophrenic patient.