Freya conducted a laboratory experiment to investigate the effect of caffeine on memory. She used an independent groups design where 10 participants drank a high-caffeine energy drink and 10 participants drank still water. Each participant was then given exactly 2 minutes to memorise a list of 20 abstract words before being asked to recall as many as possible. Freya used opportunity sampling, selecting the first 20 students she met in the university library during exam week to take part in the study.
Explain one improvement that Freya could make to her investigation.
Practise Edexcel A Level Psychology Synoptic review of studies with exam-style questions for A Level Psychology. 38 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.