The student clearly states the independent variable, tobacco use in individuals over 65, and the dependent variable, the prevalence of Parkinson's disease diagnosis in the United States during 2017, in the research question. However, the student does not describe the method of analysis or provide a clear explanation of the techniques used for measuring these variables, which is a significant oversight. While the background theory is well-developed and relevant, there are gaps in the explanations regarding sampling techniques, controlled variables, and ethical considerations. Additionally, the methodology lacks sufficient detail to ensure reproducibility. Overall, while the student presents a coherent research question and methodology, improvements are needed in clarity and specificity to enhance the investigation's rigor.
