A chronobiologist investigated the impact of blue-light filtering glasses on sleep latency (the time taken to fall asleep). A group of 15 participants had their sleep latency monitored for a week while wearing standard clear-lens glasses in the evening, and then had their sleep latency monitored for another week while wearing blue-light filtering glasses in the evening.
Outline one strength of using a repeated measures design in this study.
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.