Hello, Azumi.

For systematic reviews and meta-analyses, according to PRISMA and Cochrane guidelines, we must use at least the following 3 databases: PubMed, Cochrane and Embase. If you do not have access to any of these, another colleague from your research or group who may have access can carry out the search for you and send you the file with the exported data, for example in RIS format for you to import into the data manager. If anyone you know can do this for you, you can consult the Cochrane Handbook for Systematic Reviews of Interventions to learn how to proceed.

If you have any question, please let me know.

I second what Caroliny Hellen Azevedo da Silva said. You need to either find a collaborator or a librarian who can help you to access these databases. There may also be some plans from these company to provide you a temporary access for a specific cost.

Good luck!

Thank you so much for your comments, Caroliny Hellen Azevedo da Silva and Sébastien Buczinski .

I have further questions.

- I am wondering if Scopus can serve as a substitute for Embase.

- To my understanding, we can collect paper on clinical trials from Cochrane. My research is focusing on the distribution of clinical stages of certain cancers in real-world setting, so I am considering Cochrane may not be suitable. Is it correct?

I appreciate your comments very much.

I am not an expert in human medicine (my focus is veterinary species). I would recommend you to check to several systematic reviews on your area of specialty to see which databases were selected. This would be a quick way to determine an effective strategy. Do no forget to include your librarian on board, they know a lot on these aspects in general and are very valuable collaborators on any systematic review projects!

Embase is, as I understand, one of the backbones of Scopus. There might be an issue in how the advanced search options and features of Embase (e.g. hierarchy of terms) function in Embase.