Describe Action with the Right Preposition: By vs With

Word choice bears a lot of weight in scientific and medical writing. The words you choose reflect the accuracy of your content and the caliber of your credibility, two important qualities in science.

Some authors focus on choosing the right major words, such as nouns and verbs. But they may neglect minor words, such as prepositions. These words are just as important for accuracy as major words.

A preposition is a word that links nouns and pronouns to form phrases that show direction, time, place, location, or spatial relationships. Some common prepositions include in, at, on, under, over, before, after, by, and with.

In scientific and medical writing, some authors will use the prepositions by and with interchangeably. Although both words show how something can be done, they have different meanings.

By explains someone’s action or who performed the action. With explains what action was performed or what was used to perform the action.

Examples

Data was analyzed by the statistician.

Data was analyzed with SPSS software.

In some cases, you can use by to describe a method of doing something. In these cases, you need to pair the word by with a gerund (an “-ing” word).

Examples

We started the experiment by treating the cells with the drug.

We assessed whether the patient had a heart attack by measuring troponin T.

Who vs What

With and by are common prepositions, but they have slightly different meanings. By indicates who performed the action, whereas with indicates what was used to perform the action.