Final answer:
A psychologist conducting a study with strict diagnostic criteria and random assignment to treatment or control groups is carrying out a randomized controlled trial in clinical psychology. The study aims to assess the effectiveness of cognitive therapy for depression, grounded in the principles of cognitive psychology.
Step-by-step explanation:
The psychologist described in the scenario appears to be conducting a randomized controlled trial (RCT) to evaluate the efficacy of cognitive therapy in the treatment of depression. Patients are carefully selected based on strict diagnostic criteria and then randomly assigned to either the treatment group receiving cognitive therapy or a control group that may receive a placebo or no treatment. This research method is a hallmark of clinical psychology and is designed to minimize bias and provide reliable results on the effectiveness of therapeutic interventions.
Cognitive therapists aim to help patients identify and change dysfunctional thinking patterns that contribute to depressive symptoms. This approach is grounded in the principles of cognitive psychology, positing that thoughts, feelings, and behaviors are interconnected. The comparison to a control group helps in distinguishing the therapeutic benefits of cognitive therapy from possible placebo effects.
Studies such as the one by DeRubeis et al. (2005) have contributed to understanding the potential of cognitive therapy for managing moderate to severe depression. Such research provides a scientific basis for treatment choices in the clinical psychology field, where professionals focus on diagnosing and treating psychological disorders.