Comma usage

Last revised by Henry Knipe on 24 May 2017

The serial, series, Oxford, or Harvard comma is the addition of a comma placed immediately before the coordinating conjunction (usually and or or). In Radiopaedia, this should be used when composing lists within body text, to aid consistency of style and reduce ambiguity.


  • CT, MRI, or plain radiograph not CT, MRI or plain radiograph.

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