A clinical psychologist investigated the effectiveness of two sleep-induction techniques on sleep onset latency (the time taken to fall asleep, measured in minutes). One group of participants used Progressive Muscle Relaxation (PMR) and another group used Guided Imagery.
The standard deviation of the sleep onset latency (in minutes) for each group is shown below:
| Standard deviation | |
|---|---|
| Progressive Muscle Relaxation (PMR) | Guided Imagery |
| 11.8 | 3.5 |
Explain what the standard deviations from this study inform us about the impact of these techniques on sleep onset latency.
513 exam-style questions on OCR A Level Psychology Data recording, analysis and presentation. Each one has a worked solution and a mark scheme showing where the marks go.