The Generalizability of the Confirmation Bias Among School Psychologists

Abstract

Research has highlighted the possibility of bias in special education decision-making practices. This study explored the potential biasing effects of prior special education placement (and associated diagnostic label) on a national sample of school psychologists. A total of 240 randomly selected NASP members were asked to make diagnostic and placement decisions in response to fictitious, written case studies that were mailed to them. Each psychologist received one of four case studies that varied the referred child's educational placement (special vs. regular class) and current psychological test results (LD vs. normal). Eighty-eight school psychologists returned completed materials. The findings indicated that the school psychologists' decisions were not biased by knowledge of the child's prior special education placement but were influenced appropriately by current psychological test results. School psychologists who reevaluated a child who had been previously placed in a resource program for learning disabled students, but who currently demonstrated average academic functioning, were likely to re-classify the child as non-handicapped and recommend return to regular class programs. The findings question the generalizability of theories of a 'confirmation bias' set among school psychologists.