Which word is incorrect in the following sentence: The nurse's notes in the medical record indicate the patients pain was severe?

The word "patients" in the sentence is incorrect because it is missing the appropriate possessive form to indicate that the pain belongs to the patient. The correct term should be "patient's," indicating single ownership, as it refers to the pain of one specific patient. In this context, using the possessive form clarifies that the pain being referenced is that of a singular patient.

The other words in the sentence—"notes," "was," and "nurse's"—are correctly used. "Notes" is correctly plural to reflect multiple entries, "was" appropriately indicates past tense, and "nurse's" is correctly possessive to show that the notes belong to the nurse. Thus, changing "patients" to "patient's" makes the sentence grammatically correct.