After you remove duplicate citations, you can start screening the articles. You'll use your inclusion and exclusion criteria to decide which articles to keep and which articles to discard.

In order to help reduce bias, it's best if at least two researchers review the articles individually. If the two researchers don't agree, a third researcher can review and make the final decision. You should use this process for screening titles and abstracts and when screening full text articles.

How this works in practice

You have 4 researchers on the team--AA, BB, CC, and DD. You have 400 citations to review after removing duplicates. Using the Excel spreadsheet, you could divide up the review like this:

Rows 2-100 (row 1 is the header): AA and BB review; CC reviews if there's a disagreement

Rows 101-200: BB and CC review; DD reviews if there's a disagreement

Rows 201-300: CC and DD review; AA reviews if there's a disagreement

Rows 301-400: DD and AA review; BB reviews if there's a disagreement

There are different ways to work through the review. One way could be to make a copy of the Excel spreadsheet for each of the reviewers, review your assigned rows independently, then send your spreadsheet to the third reviewer. For example, CC would review spreadsheets from AA and BB and resolve any disagreements. You could also do this in a shared Google sheet, which seems easier, but you want to be careful about seeing decisions made by your co-reviewer and having that influence your own decision.

Document everything!

When you write your Methods section, you'll need to include some text about how the screening process was done (PRISMA #8 , PRISMA-ScR #6).