Reading focus
Syllabus: How Do We Know When Psychotherapy Helps—or Harms?
Connect each control condition to the hypothesis and to the care participants actually receive.
Why you’re reading it. Choose a comparison that can answer the intended question about benefit.
A question to consider. Would adding therapy to usual care answer the same question as comparing it with an equally credible alternative therapy? Specify the claim each design could support.
Why this reading
The comparison condition helps define the question a trial can answer. Mohr and colleagues explain how waiting, usual care, attention, treatment components and active alternatives can support different inferences. They also ask how a control is delivered, not simply what it is called.
Before you read
Random assignment aims to make groups comparable before treatment. It does not make two interventions equally credible or equally well supported. Treatment fidelity concerns whether the planned intervention is delivered as intended.
Read for
- Identify the question addressed by each comparator and which alternative explanations remain.
- Examine the proposed balance among the stage of research, feasibility, statistical power and the interests of patients and other stakeholders.
Consider afterwards
- Design two different comparisons for one intervention and state the conclusion each would support.
- How could unequal therapist training or supervision change the meaning of a treatment comparison?
Editorial context
This is a methodological argument with examples and recommendations, not a systematic test of every design choice. Its phase-based framework makes judgments about acceptable uncertainty and risk that deserve scrutiny. Usual care varies across settings, while attention and expectations can contribute to outcomes themselves. No comparator answers every question about benefit, mechanism and practical value.