A clinical psychologist wants to investigate the effectiveness of a new cognitive therapy for anxiety compared to a standard relaxation therapy. To minimise investigator effects during the assessment of the participants' post-therapy anxiety levels, which of the following research techniques should the psychologist use?
Randomly allocating participants to either the cognitive therapy group or the relaxation therapy group using a computer program.
Ensuring that the clinical researcher who conducts the post-therapy interviews is unaware of which treatment each participant received.
Counterbalancing the order in which the two therapies are delivered to each participant over the study's duration.
Ensuring that participants are kept unaware of whether they are receiving the experimental cognitive therapy or the standard relaxation therapy.
644 exam-style questions on OCR A Level Psychology Research methods and techniques. Each one has a worked solution and a mark scheme showing where the marks go.