Anna is majoring in public health. She is designing an epidemiological study to examine the relationship between alcohol consumption and academic performance at her university. In addition to ensuring that she has a large enough sample size, what strategy should she take to make sure her conclusions are accurate

She should ensure that subjects are randomly chosen from the sample group to prevent biases. She should ensure that there are no confounders in her study or that confounders are accounted for, for example, age or year of study. Older students would be more likely to consume alcohol and also be more likely to have better academic performance, for example.