The Study That Would Not Replicate
A Year 12 student reads a blog claiming that students who chew gum during study score 15% higher on tests. The blog cites one study of 22 volunteers, run by a researcher who also sells gum, with no control group and no random allocation. The student wants to design a class experiment to test the claim. Her teacher insists on ethical approval, a control group, and random allocation. The student argues that a control group is unnecessary because 'everyone knows gum helps focus' and that withholding gum from classmates is unfair.
1. Evaluate the original blog study using at least three research-method concepts, and explain why the student's proposed experiment would be stronger.
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Original study weaknesses: small sample (22) limits generalisability and statistical power; no control group means practice, expectancy and placebo effects are uncontrolled; no random allocation means individual differences (e.g., prior ability) confound results; researcher conflict of interest threatens objectivity and may bias reporting. The student's design adds a control group, random allocation to gum/no-gum, and ethical approval, which allows causal inference and reduces bias. A judgement call: even a stronger design needs a clear operational definition of 'focus' (e.g., score on a 10-minute attention task) and blinding where possible, otherwise expectancy remains.
2. Address the student's ethical objection about withholding gum, and outline how she should obtain consent and handle results.
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Withholding gum is not harmful; it is a low-risk comparison condition, so fairness is satisfied if participants are debriefed and, if the gum condition proves beneficial, control participants are offered the chance to try it. Consent: informed consent from students and, because they are minors, from parents/guardians; explain purpose, procedure, duration, right to withdraw at any time without penalty, and confidentiality (codes, not names). Results should be reported honestly, including null results, and the class should be told the blog's claim was not supported if that is the finding. A judgement call: the exam rewards distinguishing 'no risk' from 'no ethics needed' - ethics still requires consent, withdrawal rights and debriefing.