The study was conducted in the Family Medicine
Centre at Mount Sinai Hospital, Toronto, from December
1995 to February 1997. The centre is a family medicine
residency training site affiliated with the University
of Toronto and handles approximately 30 000 outpatient
primary care visits per year. The medical staff comprises
8 full-time family physicians, 5 part-time communitybased
physicians and 18 residents. All medical staff enrolled
patients. The study was approved by an ethics review
committee of the University of Toronto.
Patients aged 3 years or more were eligible for the
study if, in the opinion of the physician, they had a new
URTI. Patients were excluded if they had been taking antibiotics
in the previous week or were immunocompromised.
Patients or parents (in the case of children aged 16
years or less) were approached by the treating physician,
and those giving written consent were enrolled. A standardized
encounter form was completed by each physician
at the time they assessed a patient, and a single throat
swab was obtained in the physicians’ usual manner.