Minja 2006.

Methods	Three‐arm, non‐blinded, cluster‐RCT (randomised by school), with 1 month duration of treatment and 3‐ to 4‐month duration of follow‐up
Participants	Location: Tanzania, 24 sites Setting of recruitment and treatment: 24 schools in 3 different socially comparable districts in the Dar Es Salaam region of Tanzania. Study published in 2006. Sample size: Number randomised: 74 in systemic antibiotics PLUS topical antiseptics, 130 in topical antiseptics alone, 124 in no treatment group Number completed: 74 in systemic antibiotics PLUS topical antiseptics, 130 in topical antiseptics alone, 124 in no treatment group Participant (baseline) characteristics: Age: mean 11.8 years (± 2.7 years) Gender (F/M): 175 (53%)/153 (47%) Main diagnosis: children with a history of ear discharge in one or both ears for 3 months or more at the first examination High‐risk population: unclear Cleft palate (or other craniofacial malformation): Not reported (NR) Down syndrome: NR Indigenous groups (Australian Aboriginals/Greenland natives): NR Immunocompromised: NR Diagnosis method: Confirmation of perforated tympanic membrane: yes. All children had otoscopy at entry to the study and perforation of ear membrane was part of the diagnostic criteria used. Presence of mucopurulent discharge: NR Duration of symptoms (discharge): at least 3 months (inclusion criteria) Other important effect modifiers: Alternative diagnosis of ear discharge: NR Number who have previously had grommets inserted: NR Number who have had previous ear surgery: NR Number who had previous antibiotic treatment for CSOM: NR Inclusion criteria: Children with a history of ear discharge in one or both ears for 3 months or more at the first examination Exclusion criteria: None listed
Interventions	Systemic antibiotics + topical antiseptics (n = 74): amoxicillin (unspecified dose/body weight) for 10 days PLUS boric acid in alcohol ear drops (unspecified concentration) for 1 month. No further information about dosage or frequency of administration. Topical antiseptics (n = 130): boric acid in alcohol ear drops (unspecified concentration) for 1 month. No further information about dosage or frequency of administration. No additional treatment (n = 124): no additional treatment Concurrent treatment for all groups: dry mopping completed daily for 1 month, specific technique not specified. Dry mopping and instillation of boric acid ear drop done by "one teacher ... trained to dry mop the children's ear canal and instil the ear drops" in each school.
Outcomes	Outcomes of interest in the review: Primary outcomes: Resolution of ear discharge ('dry ear'), measured at between 2 to 4 weeks and after 4 weeks by otoscopic evaluation Secondary outcomes Hearing (measured as change in pure tone (air conduction)) hearing threshold from baseline or at endpoint) Suspected ototoxicity
Funding sources	"SAREC/SIDA Sweden, who supported the study financially" (SAREC is a department of the Swedish International Development Cooperation Agency (SIDA))
Declarations of interest	Not specifically mentioned, although the paper does say "Dr. Leif Ingvarsson [one of the authors] was responsible for securing the funds."
Notes	Unit of randomisation: school Methods for including patients bilateral disease: 'dry ear' only counted if both ears were dry. Did not report how many patients had bilateral ear disease. There were a total of 371 non‐intact tympanic drums evaluated for hearing tests. Study did not report how many schools were using each treatment
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Randomised controlled trial" (in abstract). Discussion section stated, "All the children with CSOM in the same school were put in the same treatment group (1, 2 or 3)". Comment: there is no information about randomised sequence generation
Allocation concealment (selection bias)	High risk	Quote: "Randomly selected primary schools…" "All the children with CSOM in the same school were put in the same treatment group (1, 2 or 3)". Comment: although the abstract indicates that the study was a randomised controlled trial it then goes on to state that the schools were "randomly selected primary schools", which provides doubt regarding whether the schools in the paper were randomised to treatment group (RCT) or just randomly selected from a list of schools (comparative cohort study). If the schools were randomly allocated to treatment group it is not clear whether the people completing the allocation knew to which group each school was going to be allocated.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "All the children with CSOM in the same school were put in the same treatment group (1,2 or 3). Children in one school had no contacts with children from other schools included in the investigation." Comment: a single teacher administered all ear instillation and dry mopping in each school. Not clear if patients and teachers were aware of all treatment options. Unclear how this affects compliance with antibiotics etc.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "otoscopically examined". "Two ORL specialists … hearing pathologists". Comment: team composition described but no description of who evaluated the outcomes and whether they were aware of the treatment received. This is high‐risk as the whole school received the same treatment and patients were not blinded.
Incomplete outcome data (attrition bias) All outcomes	High risk	Comment: loss to follow‐up was uneven across groups, and higher for groups with more treatment. This was 17/74 (23%) in the group with amoxicillin (systemic antibiotics), 25/130 (19%) in the group with boric acid ear drops, and 14/124 (11%) in the group with only dry mopping. Reasons for dropout were not evaluated, but very similar for the 1 month and 3 to 4 months follow‐up.
Selective reporting (reporting bias)	Unclear risk	Comment: no protocol for the trial could be found on the clinicaltrials.gov website. The primary outcome (number with discharging ears) is measured by the patient yet the hearing results are measured on a 'by ear' basis.