Dr. Aris investigated whether receiving positive sleep-quality feedback on a smartwatch in the morning improves subjective alertness. He recruited participants using self-selected (volunteer) sampling via an online health forum.
Dr. Aris compared two conditions using an independent groups design. In Condition 1, participants received a notification stating they had achieved an 'Excellent Sleep Score of 92%' upon waking. In Condition 2, participants received no morning sleep notification at all.
Explain one strength of Dr. Aris using an independent groups design in this investigation.
638 exam-style questions on Edexcel A Level Psychology Methods. Each one has a worked solution and a mark scheme showing where the marks go.