Do you know how to use the Oxford Comma?

• Punctuation is important for clarity.
• Clarity is especially important for academic manuscripts.
• Using the Oxford comma increases the clarity of your science manuscript.

What is the Oxford Comma?

The Oxford comma is the comma used after the penultimate item in a list of 3 or more items, before the conjunction "and" or "or". Those who oppose its use argue that it is redundant and adds unnecessary clutter to a sentence. They argue that the conjunction "and" or "or" is sufficient to separate the items in a list, and that the Oxford comma is superfluous. In the vast majority of cases, however, the Oxford comma provides clarity and precision to a sentence. By using the Oxford comma, the writer is making it clear that each item in a list is separate and distinct.

Importance of the Oxford Comma

Proper punctuation is critical for clarity, as made very clear in the very popular book, Eats, Shoots & Leaves by Lynne Truss. In this humorous book about proper punctuation, Truss cleverly demonstrates why commas are important for clarity. The giant panda eats shoots and leaves. That is, its diet comprises bamboo shoots and leaves. Improper addition of commas, however, changes the meaning of this sentence entirely, making the panda seem to be dangerous. In the following sentence, "The panda eats, shoots, and leaves.", the panda is understood to eat its meal, take aim with an arrow or weapon, and then leave the area.

Know When to Use the Oxford Comma

In English-language editing of science manuscripts, punctuation is especially important for both clarity and conciseness. Proper punctuation can help you convey the take-home message of your manuscript, while at the same time, improper punctuation can lead to complete confusion. The use of the Oxford comma is a controversial topic among writers and editors, with some arguing that it is unnecessary and others advocating for its consistent use. Here we argue why the Oxford comma is important for clear and effective communication in science manuscripts.

Let’s look at the following sentence.

Duloxetine and citalopram may be prescribed for postpartum depression. We investigated the effects of these antidepressants, alcohol and barbiturates in an animal model of postpartum depression.

In this sentence, the lack of an Oxford comma after the word alcohol reads as though these substances, alcohol and barbiturates, are examples of antidepressants. The simple addition of the Oxford comma clarifies this sentence: Four different drugs are being investigated for their effects on postpartum depression: the antidepressants duloxetine and citalopram, alcohol, and barbiturates. The Oxford comma removes the ambiguity. The Oxford Comma allows you to be concise while keeping your meaning clear. On the other hand, knowing when not to use the Oxford comma is just as important as knowing when to use it. Consider the following example:

The effects of NMDA antagonists, MK-801 and DxM were evaluated in a model of chronic pain.

MK-801 and DxM are examples of NMDA antagonists. In this case, only 2 drugs are being studied, both of which are NMDA antagonists. Inserting an Oxford comma would be confusing because it would lead the reader to think that 3 different types of drugs were being evaluated – 1) NMDA antagonists, 2) MK-801, and 3) DxM. The Oxford comma, therefore, removes ambiguity by offering a distinction between different things.

By using the Oxford comma, a writer can demonstrate attention to detail and a commitment to clear and precise communication. In academic writing, for example, the Oxford comma may even be required by certain style guides.

The use of the Oxford comma is an important tool for clear and effective communication. As such, we strongly recommend the use of the Oxford comma in all forms of writing.

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