The Actuarial Turn in the Science of Learning Disabilities

Abstract

In the mid-1970s, Donald Hammill and his colleagues authored three scathing critiques of the two most trusted scientific traditions of learning disability treatment — movement education and psycholinguistic training (Hammill, 1972; Hammill & Larsen, 1974; Hammill, Goodman, & Wiederholt, 1974). These critical reviews of research rejected the older model of clinical science that had served as the foundation of the field of learning disabilities and celebrated an actuarial form of research. Was Hammill actually proclaiming a change in the orientation toward scientific research, a paradigm shift involving philosophical commitments and methodological practices? This article explores the history of both the foundational clinical science and the new actuarial science that rose to prominence in the field of learning disabilities in the 1970s.