Final answer:
By the 1980s, psychotherapy research primarily aimed to evaluate the empirical efficacy of therapeutic approaches, influenced by foundational figures such as Freud and Rogers as well as the rise of behaviorism and cognitive therapies.
Step-by-step explanation:
By the 1980s, the primary goal of psychotherapy research was to explore the empirical efficacy of therapeutic approaches (C). This focus meant researchers were interested in systematically studying and validating the effectiveness of different types of psychotherapy. Prior to this, influential figures like Sigmund Freud and Carl Rogers had established the foundation for understanding and treating psychopathology. Freud's psychoanalysis and Rogers' client-centered therapy shaped the field of psychology, with the latter becoming especially influential in many clinicians' practices. Freud believed that much of our psychological issues stemmed from unconscious factors and childhood experiences. In-depth, long-term analysis was typical of his approach. Rogers, on the other hand, emphasized the importance of the therapeutic relationship and the client's perspective.
By the time the 1980s arrived, the influence of both behaviorism and the cognitive revolution had introduced more structured and measurable forms of psychotherapy, such as cognitive-behavioral therapy. Consequently, the need arose to evaluate these treatments rigorously to assess their outcomes and prove their validity and effectiveness. This shift also marked a broader movement in psychology towards understanding and addressing mental health issues through empirical research and evidence-based practice.