A systematic review of healthcare research using Google Trends found that the tool is increasingly used across various health topics, including infectious diseases, mental health, and population behavior. However, many studies lack proper documentation, limiting reproducibility. The review analyzed 70 studies published between 2009 and 2013, showing a seven-fold increase in publications. Studies were categorized into four topic domains and three study aims: causal inference, description, and surveillance. While 92% of surveillance studies validated results against external data, only 7% of articles provided sufficient documentation for reproducibility. The review highlights the need for clear search strategies and methodological documentation to ensure reliability. Despite its potential, Google Trends faces challenges in data accuracy and interpretation due to limited user input details and the lack of standardized guidelines. The study recommends a checklist for future research to improve transparency and reproducibility. While Google Trends can provide valuable insights into health trends, its use requires careful consideration of methodological rigor and validation to ensure reliable results. The review emphasizes the importance of clear documentation and validation processes to enhance the credibility of research findings using this tool.A systematic review of healthcare research using Google Trends found that the tool is increasingly used across various health topics, including infectious diseases, mental health, and population behavior. However, many studies lack proper documentation, limiting reproducibility. The review analyzed 70 studies published between 2009 and 2013, showing a seven-fold increase in publications. Studies were categorized into four topic domains and three study aims: causal inference, description, and surveillance. While 92% of surveillance studies validated results against external data, only 7% of articles provided sufficient documentation for reproducibility. The review highlights the need for clear search strategies and methodological documentation to ensure reliability. Despite its potential, Google Trends faces challenges in data accuracy and interpretation due to limited user input details and the lack of standardized guidelines. The study recommends a checklist for future research to improve transparency and reproducibility. While Google Trends can provide valuable insights into health trends, its use requires careful consideration of methodological rigor and validation to ensure reliable results. The review emphasizes the importance of clear documentation and validation processes to enhance the credibility of research findings using this tool.