Which of the following is NOT a criterion in CENTOR's criteria for throat culture determination?

CENTOR's criteria is a clinical guideline used to assess the likelihood of streptococcal pharyngitis and determine the need for a throat culture or treatment. The criteria are comprised of four specific factors that help clinicians evaluate the probability of streptococcal infection in patients presenting with sore throat.

The presence of cough is not included in CENTOR's criteria. The rationale for this is that a cough is more indicative of viral infections, while the other criteria focus on signs more commonly associated with bacterial infections, particularly streptococcus. When evaluating a patient for the likelihood of streptococcal pharyngitis, clinicians look for exudate on the tonsils, tender or swollen lymph nodes, and fever, all of which are considered strong indicators of bacterial infection.

Thus, cough does not fit into the framework of CENTOR's criteria, making it the correct answer in identifying what does not belong among the factors that influence the decision to perform a throat culture.