Nwokoye 2015.

Study characteristics
Methods	3‐arm, non‐blinded, parallel‐group RCT, with 7 to 10 days duration of treatment and unspecified duration of follow‐up
Participants	Location: Nigeria; Ikeja state capital of Lagos Setting of recruitment and treatment: Lagos State University Teaching Hospital, single site. Unclear when this was conducted (poster published in 2012). Sample size: Number randomised: 27 in intervention, 27 in comparison Number completed: not reported Participant (baseline) characteristics: Age: 5 months to 10 years (52/82, 63%, under 2 years) Gender (F/M): not reported Main diagnosis: otorrhoea for at least 3 months High‐risk population: no Cleft palate (or other craniofacial malformation): not reported Down syndrome: not reported Indigenous groups (Australian Aboriginals/Greenland natives): 0 Immunocompromised: not reported Diagnosis method: Confirmation of perforated tympanic membrane: no, otoscopy used, but no requirement for perforated tympanic membrane (scarred, dull and/or retracted tympanic membrane) Presence of mucopurulent discharge: not reported Duration of symptoms (discharge): "minimum 3 months" Other important effect modifiers: Alternative diagnosis of ear discharge: not reported Number who have previously had grommets inserted: not reported Number who have had previous ear surgery not reported Number who had previous antibiotic treatment for CSOM: not reported Inclusion criteria: CSOM was diagnosed based on “persistent symptoms for at least three months, with a scarred, dull and/or retracted tympanic membrane on otoscopic evaluation. Current and previous painless otorrhoea, possibly accompanied by cold, sore throat and cough, aided the diagnosis of CSOM” Exclusion criteria: Cholesteatoma History of antibiotic therapy 2 months prior to presentation at clinic
Interventions	Amoxicillin clavulanate (n = 27): amoxicillin 80 mg/kg/day was given orally in 2 divided doses for 7 to 10 days, dose of clavulanate acid not specified Amoxicillin group(n = 27): amoxicillin 80 mg/kg/day was given orally in 2 divided doses for 7 to 10 days Concurrent treatment: "aural toilet was initiated at the clinic with warm saline solution. The child's care giver was advised to continue the treatment four times daily using dry cotton wool wisps."
Outcomes	Outcomes of interest in the review: Primary outcomes: Resolution of ear discharge or "dry ear" (whether otoscopically confirmed or not) measured at unspecified time point Secondary outcomes Not reported
Funding sources	No information provided
Declarations of interest	No information provided
Notes	Methods for reporting outcomes of patients with bilateral disease: not specified. Unclear whether there were patients with bilateral disease. There was third arm studied that had treatment based on culture and antibiotic sensitivity results (n = 28).
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "the CSOM patients were randomly place into..." The following are published authors' replies: Response 1: "The study was a randomized clinical trial. Patients diagnosed for CSOM were randomly placed into one of the three groups based on informed consent of the parents or guardians who agreed for their ward to be enrolled within a specified group. Parents that gave written consent for inclusion was asked to choose two out of the three groups their ward could be placed. It was based on this information that the patients were distributed into case groups trying as much as possible to have a binomial distribution of our sample population." Response 2: "The assignment into study groups under each patient category was done by random number table." Comment: there was no mention of randomisation in the initial paper, but authors the suggested it was randomised in the published responses and replies to our queries.
Allocation concealment (selection bias)	Unclear risk	Comment: no information about allocation concealment provided.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Comment: no description of blinding or placebo. However, both intervention arms received antibiotics. Unclear whether lack of blinding could have affected adherence or other aspects significantly.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Comment: no description of blinding or placebo.
Incomplete outcome data (attrition bias) All outcomes	High risk	Quote: "When for strong clinical judgment it was necessary to withdraw a child from the study and managed as an independent patient that was done and the patient was excluded from the study." Comment: further information from the authors suggested patients could be excluded from the analysis. Loss to follow‐up was not reported.
Selective reporting (reporting bias)	Unclear risk	Comment: could not access the protocol. Very little information about outcomes in the Methods section.