A sports psychologist asks members of a local athletics club to complete a questionnaire about how often they completed the club's full warm-up before training during the previous four weeks.
Explain one weakness of using a questionnaire in this investigation.
139 exam-style questions on OCR GCSE Psychology 7.2 Doing Research, covering 7.2.1 Experiments, 7.2.2 Interviews, 7.2.3 Questionnaires (Surveys), 7.2.4 Observations, 7.2.5 Case Studies, and 7.2.6 Correlations. Each one has a worked solution and a mark scheme showing where the marks go.