Most universities allow a certain percentage of similar content, usually around 10-15 per cent, but anything beyond the specified limit is not acceptable. The rule usually applies for the entire dissertation and the literature review section is not an exception. Therefore, it is very important to run a plagiarism check on the complete dissertation before you submit it so that you are aware of the parts that have similar content. Even if you have not intentionally copied text from other sources, you might unknowingly or unintentionally have used words or phrases that are similar to other published sources. Once the software identifies the parts that are similar, you can easily reword or paraphrase those sentences. That way, you will be able to avoid accidental plagiarism.