Writing and Style Basics
5 | How to Avoid Comma Splices
Key Point
Best Practices
Scientific papers contain numerous clauses, both independent and dependent, which are joined by various punctuation marks and connecting words. Independent clauses are those that form a complete sentence with a subject and verb. The examples below illustrate the incorrect and correct ways that independent clauses can be connected by comma splices, periods, semicolons, and comma–conjunction combinations:
- INCORRECT: Several tumors decreased in size, a few tumors showed no change.
- CORRECT: Several tumors decreased in size. A few tumors showed no change.
- CORRECT: Several tumors decreased in size; a few tumors showed no change.
- CORRECT: Several tumors decreased in size, but a few tumors showed no change.
While comma splices are fairly common in poetry and fiction—one of the most famous splices by Charles Dickens reads “It was the best of times, it was the worst of times …”—use of this grammatical technique should be avoided in scientific writing. In scientific writing, the best approach is to maintain a formal tone with strict adherence to grammatical conventions.