Jackson 1973.

Study characteristics
Methods	RCT Double‐blinded
Participants	Number of participants randomised: 314 (95 negative culture excluded from analysis) Number of participants evaluated: 207 (70%) Number of dropouts: 12 reported Setting: not described Age: not described Diagnosis: throat culture Inclusion criteria: child in weight range 11.4 to 45.4 kg, pharyngitis, positive culture or white blood count > 10,000 Exclusion criteria: allergy to penicillin or lincomycin, received any antibiotics within previous 6 weeks
Interventions	Groups: clindamycin daily dose 150 to 450 mg (n = 156); ampicillin daily dose 750 to 2000 mg (n = 158) Duration of treatment: 10 days Duration of follow‐up: 26 to 28 days post‐therapy
Outcomes	Adverse effects Bacteriological outcomes
Notes	Funding: Upjohn Company Ethics approval: not mentioned ITT for adverse events
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Reported as "randomised", but no description of randomisation sequence
Allocation concealment (selection bias)	Low risk	"Labels for each group were randomised, sealed in sequentially numbered envelopes,..."
Blinding (performance bias and detection bias) All outcomes	Low risk	See above.
Incomplete outcome data (attrition bias) All outcomes	High risk	95 negative cultures excluded after randomisation; 12 positive cultures excluded due to failure to return first follow‐up culture (clindamycin 7 and ampicillin 5). 30% postrandomisation dropout
Selective reporting (reporting bias)	Unclear risk	Only clinical outcome for poststreptococcal sequelae ITT for adverse events
Other bias	High risk	Funding: Upjohn Company