编辑一篇给定的英文文章，使其更简洁清晰。
输入文章: The purpose of this study is to investigate the impact of social media on mental health. A survey was conducted among 300 students at a local university. The results of the survey showed that social media indeed has negative effects on mental health.
This study examines the impact of social media on mental health via a survey of 300 students at a local university. According to the results, social media has a harmful effect.