Mayes 2001a.

Study characteristics
Patient sampling	Cross‐sectional study Retrospective design Sample: unclear Direct comparison of different RADTs: no Direct comparison of several throat culture techniques: no Person performing the throat sample: not reported Exclusion if recent antibiotics use before inclusion: no Clinical selection of patients: implicit criteria (RADTs were not used for all patients presenting with pharyngitis; different physicians used varying individual criteria to determine whether or not to use the RADT or throat culture as the primary diagnostic test) Presenting signs and symptoms: unclear Age range for inclusion: not reported
Patient characteristics and setting	Sample size: total 4847 Age (distribution): not reported GAS prevalence according to culture (with 95% confidence interval): 28.8% (assuming all RADT positive results are true positives; 95CI not reported) Country of study: USA Sex (% of girls): 45% Clinical severity assessment: none Clinical setting: office‐based (laboratory records of the Elmwood Pediatric Group) Single‐centre study
Index tests	Throat swab: 2 different swabs (1 swab for performing the RADT, 1 swab for culture) Commercial name of the RADT: Qtest (Becton Dickinson) Type of RADT: EIA (liposomal test)
Target condition and reference standard(s)	Throat culture medium: not reported Atmosphere of incubation: not reported Duration of incubation: not reported GAS confirmation: not reported Number of plates inoculated: not reported Assessment of GAS antibody response: no Relevant details: throat culture technique not described
Flow and timing	No follow‐up
Comparative
Type of study	Journal article
Notes	We sub‐divided the study into 2 time periods (Mayes 2001a and Mayes 2001b) to take into account the fact that different criteria were used to determine whether or not a RADT should be performed, and because different RADTs were used during those 2 time periods. Funded in part by an academic grant (Strong Children's Research Center, Summer Student Scholar Program, University of Rochester). Throat culture performed only for children with negative RADT results (partial verification).
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	No
Was it a cross‐sectional study or a RCT?	Yes
Were selection criteria clearly described (at least presenting signs and symptoms and age limits for inclusion)?	No
Was clinical selection of patients avoided?	No
Were patients seen in an ambulatory care setting?	Yes
		High	High
DOMAIN 2: Index Test All tests
Were the RADT results interpreted with blinding of the results of culture?	Yes
Was the type of the RADT mentioned (EIA or OIA)?	Yes
Were RADTs conducted during consultation time?	Yes
		Low	Low
DOMAIN 3: Reference Standard
Were culture results interpreted with blinding of the results of the RADT?	Unclear
Is the throat culture method likely to correctly identify GAS (laboratory culture on a blood agar plate during 48 hr)?	Unclear
Were the culture medium, atmosphere, duration of incubation and GAS‐confirmation technique described?	No
		High	High
DOMAIN 4: Flow and Timing
Was the delay between the performance of the RADT and throat culture plating less than 48 hours?	Unclear
Did all patients receive a throat culture?	No
Did patients receive the same throat culture method?	Unclear
Were undetermined/uninterpretable results reported?	No
Were withdrawals from the study explained?	Yes
		High