SCHOOL-PSYCHOLOGISTS DIAGNOSES OF LEARNING-DISABILITIES - A STUDY OF ILLUSORY CORRELATION

We examined whether school psychologists based diagnoses of learning d isabilities on irrelevant data. Nationally certified school psychologi sts received case study material containing both relevant and irreleva nt information for diagnosing a learning disability. The psychologists indicated (a) the probability that the client was learning disabled, (b)their confidence in the diagnosis, and(c) their decision-making str ategy. They tended to base diagnostic decisions on false beliefs, whic h we discuss in respect to prior research on illusory correlation.