Strangert 1969.

Methods	Quasi‐randomised controlled trial
Participants	Inclusion criteria: children admitted with clinical pertussis Exclusion criteria: children who received chloramphenicol or ampicillin prior to their stay in hospital or were discharged before the course of therapy had been completed
Interventions	Treatment group: ampicillin 75 to 100 mg/kg/day divided in 4 doses for 6 days Controlled group: chloramphenicol 75 to 100 mg/kg/day divided in 4 doses for 6 days Children under 6 months of age were also given immunoglobulin against whooping cough each other day on altogether 3 occasions
Outcomes	Microbiological eradication, adverse reactions, complications (secondary infections)
Notes	This is quasi‐randomised study for treatment of pertussis. Immunisation status not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Method of randomisation: alternation of patients (each second child admitted with whooping cough was treated with ampicillin)
Allocation concealment (selection bias)	High risk	High risk
Blinding (performance bias and detection bias) All outcomes	High risk	Blinding of intervention: no. Blinding of outcome measure: no
Incomplete outcome data (attrition bias) All outcomes	High risk	Complete follow up: no
Selective reporting (reporting bias)	High risk

DTP: diphtheria‐tetanus‐pertussis 
 EST: erythromycin estolate 
 ETH: erythromycin ethylsuccinate 
 t.d.s: three times a day