Understanding Turnitin
Turnitin is text matching software that is used to help understand the originality of work submitted for assessment.
While Turnitin can highlight issues with plagiarism, there is more information available in the final report.
How Turnitin works
Every time work is submitted to Turnitin, it will be compared to other material which already exists on the database. Turnitin stores a database of sources which includes journals and books, internet materials, and work that has been uploaded to Turnitin globally.
If the text submitted to Turnitin matches other sources already entered in the database, it will be highlighted on Turnitin. It's normal to have at least some text matching in Turnitin. This does not always mean that plagiarism has occurred, and the report will be interpreted by the marker.
Turnitin reporting
After submitting work to Turnitin, a similarity report will be produced. The similarity report gives information about the text which has been matched against another entry in the database and will produce a percentage, as well as highlight sections of text.
The report needs to be interpreted to understand if plagiarism has occurred. Extensive highlighted sections should be investigated, as they may indicate that more careful paraphrasing is required.
Turnitin may highlight assignment titles, commonly used assignment forms, reference lists or bibliographies, and quotes which use single quotation marks.
Read more about interpreting the similarity report.
Types of matches you may see in Turnitin
Quotation and reference lists
In a paper which has relied heavily on quotations, the similarity score will be high. Quotes can be excluded from the similarity report, provided you haven't used single quotation marks—Turnitin doesn't recognise single quotation marks.
Reference lists
Depending on the settings, the reference list or bibliography may also be highlighted. This can be adjusted in the settings.
Large chunks of highlighted text highlighted in a single colour
If there are large sections of text that are fully highlighted in one colour, this indicates that the material matches another source in Turnitin’s database. These sections will need to be reviewed more closely.
Chunks of text highlighted in multiple colours
This indicates that a number of sources have been used within the text, but it hasn't been paraphrased correctly.
Scattered sections of highlighted text
This occurs when large chunks of material have been copied, and while there's been an attempt to paraphrase, this hasn't been done sufficiently.
Small matches
Turnitin will often pick up small matches, so it's important to check the settings and be aware of this. Course names, assignment declarations, lecturer titles, and matches of three words or more may be highlighted in the report because they already exist in the database. By carefully reviewing the report, you can distinguish what is problematic from what is simply ‘noise’. The settings can also be adjusted to prevent these small, non-problematic matches from being highlighted.