Final answer:
OPCRST is a mnemonic in medicine used to obtain a thorough history of a patient's symptoms, especially relating to pain or discomfort, and stands for Onset; Provocation, Palliative, and Positioning; Quality; Radiation; Severity; and Time.
Step-by-step explanation:
The mnemonic OPCRST stands for Onset; Provocation, Palliative, and Positioning; Quality of the discomfort; Radiation; Severity; and Time. This mnemonic is used in the medical field to obtain a thorough history of a patient's complaint or symptoms, especially when they present with pain or discomfort. Each component of OPCRST serves to gather comprehensive details about the patient's condition in order to aid in diagnosis and treatment.