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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Shawn E. Davis, PhD


The present literature review provides a brief history of psychology as a helping profession. Followed by an exploration of the core assumptions of psychological theories, the medical model as it is applied to psychology, the science of psychology, and the biopsychosocial model. An argument is made for psychology to adopt a new multicausal model for diagnosis and treatment delivery that matches psychological interventions and psychological theory. The biopsychosocial model is explored as a possible alternative to the current medical model theories of mental disease and disorder. Implications of the current medical model and alternatives are explored and discussed.