Abstract:

Common factors theory and specific ingredients theory are two contradictory theories on the contributing factors of therapeutic change in psychotherapy. This article reviews the definition of common factors theory and its two developmental pathways; explores the concepts and research advances of the specific ingredients theory through examples of empirically supported treatment; and discusses respectively the issues and debates within each of the theories. We concluded that the concepts of "common factors" and "specific ingredients" represent a temporary categorization of the contributing facts of therapeutic change, mainly through the eyes of researchers. These two concepts are largely interdependent and interchangeable; however, even a combination of them may still not be able to accommodate all factors of therapeutic change. In the future, there is a need to further understand the process and mechanism of therapeutic change; to equip our next-generation clinical psychologists with skills for both "common factors" and "specific ingredients"; and to gradually integrate these two camps into one through the promotion of evidence-based psychotherapies.

Key words: common factor, specific ingredient, therapeutic change, empirically supported treatment, evidence-based psychotherapy, integration