Q: Can references lead to an increased percentage of plagiarism in the plagiarism report?
Yes, references can lead to an increased percentage of plagiarism in the plagiarism report. Which is why they are typically excluded from the plagiarism check, as you can read here: Should references be included in a plagiarism check?
Without the references, you should aim for a number not more than 15-20%. Some other ways to reduce plagiarism through references are by using paraphrasing (where you modify the original statement while retaining the meaning) and indirect quoting (using phrases such as “said that” and “observed that” before the referenced statement. Finally, note that editors use plagiarism software only as an initial check, but use their discretion for a final call on whether the manuscript should be considered plagiarized, and if so, how much.
For more information on addressing plagiarism in manuscripts, you may refer to the following queries by other users: