Non-response and selection bias can significantly impact the validity of research findings. When individuals choose not to participate in a study, the sample may not accurately represent the population. This can lead to skewed results and erroneous conclusions. Researchers must consider the reasons for non-response and implement strategies to minimize selection bias. By understanding the implications of non-response, researchers can adjust their methodologies to address potential biases. Effective communication and outreach efforts can improve response rates and reduce the impact of selection bias on study outcomes. Overall, addressing non-response and selection bias is crucial for ensuring the reliability and relevance of research findings.