A researcher investigated the impact of blue-light filtering glasses on sleep latency (the time taken to fall asleep). A sample of 12 participants spent one week wearing blue-light filtering glasses for 2 hours before bed (Condition A) and another week wearing clear, non-filtering glasses (Condition B). The order of conditions was counterbalanced. The mean sleep latency in minutes was recorded for each participant under both conditions.
| Condition A (Blue-light filtering) | Condition B (Clear glasses) | |
|---|---|---|
| Mean sleep latency (minutes) | 22.4 | 38.6 |
Explain which statistical test the researcher could have used to analyse these data.
Practise Edexcel A Level Psychology Methods with exam-style questions for A Level Psychology. 100 questions, matched to the Edexcel A Level Psychology (9PS0) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.