Question

Robert had always heard that eating cheese before bedtime caused nightmares. He decided to use the scientific method to see if this was true. He formed a hypothesis; “Does cheese cause nightmares?” He recruited nine members of his family (parents, siblings, one uncle, and three cousins) and asked them to participate for one week. He made the following conditions; participants either had to eat cheese before bedtime (the experimental group) or not eat cheese (control group). He provided each participant with a notebook and pencil to keep next to their bed, to record if they woke in the middle of the night from a nightmare. After one week he found that of the 9 participants four, including Robert, had had nightmares during the week, all of them had eaten cheese the evening before.

Has Robert proved that cheese causes nightmares?

Critically evaluate Roberts experiment. Identify four flaws in his experimental design. For each make a suggestion as to how his experiment could be improved.

Answer 1

Yes, Robert has proved that cheese causes nightmares in this experiment but there are some flaws in his experimental design such as:

i) There is no solid proof that eating cheese at night causes nightmares. Experiment group size is very small. So, the size of the experiment group is increased from 10 to 100 or 200.

ii) The duration of exposure is also very less. So, the duration of the experiment should be increased.

iii) There is no biochemical proof of experiment. in the absence of any quantitative data and statistical evidence, the experiment is not reliable. So, the experiment should be based on some biochemical evidence.

There is another substance contained in cheese which might be pertinent here – tryptophan. It is an amino acid found in various foods, including milk, chicken, turkey and peanuts. The body uses it to produce serotonin, a chemical messenger associated with stable mood and sound sleep.

iv) The experiment is based on qualitative data and measurement. He should include some statistical calculations and quantitative data in this experiment.

There is no solid proof that eating cheese at night causes nightmares. What we can say with more certainty is that if you eat immediately before going to bed, or have over-eaten, then indigestion might give you a restless night. But it could be the case that a little cheese might even help you sleep more soundly.