Liu 2003.

Methods	Two‐arm, blinding not described, parallel‐group RCT, with 2‐week duration of treatment and follow‐up
Participants	Location: China, 1 site Setting of recruitment and treatment: outpatient department, department of Otolaryngology, Wenzhou Second People's Hospital, published in 2003 Sample size: 160 Number randomised: 87 in rifampicin, 73 in chloramphenicol Number completed: 87 in rifampicin, 73 in chloramphenicol Participant (baseline) characteristics: Age: mean 30 years (range: 12 to 65 years) Gender (F/M): 58 (38.7%)/92 (61.3%). Note: only 150 of 160 recruited patients are accounted for Main diagnosis: "patients who were diagnosed with chronic suppurative otitis media in the out‐patient department." No definition was provided. High‐risk population: unclear Cleft palate (or other craniofacial malformation): not reported Down syndrome: not reported Indigenous groups (Australian Aboriginals/Greenland natives): not reported Immunocompromised: not reported Diagnosis method: unclear Confirmation of perforated tympanic membrane: not reported Presence of mucopurulent discharge: not reported Duration of symptoms (discharge): not reported 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: Not reported Exclusion criteria: Not reported
Interventions	Group A (n = 87): rifampicin (0.1%) eye drops, through the ear canal, 3 drops, 3 times a day. Duration of treatment: 2 weeks. Group B (n = 73): chloramphenicol (0.25%) eye drops, through the ear canal, 3 drops, 3 times a day. Duration of treatment: 2 weeks. Concurrent treatment: aural toileting, "wash the ear canal with 3% H2O2 solution and dry the ear" before administration of ear drops
Outcomes	Outcomes of interest in the review: Primary outcomes: Complete resolution of ear discharge measured at 2 weeks: Quote: "Criteria for assessment of outcomes: Cured: otorrhea disappeared, mucosal hyperemia of the tympanic membrane and tympanic cavity disappeared Significantly effective: no complaints of otorrhea, no visible purulence in the ear canal and tympanic cavity, and nonvisible or slight hyperemia of the tympanic membrane and the tympanic canal Non‐effective: otorrhea persisted after 2 weeks of treatment, purulence in the external ear and tympanic cavity, and hyperemia of the tympanic membrane" The outcome was presented as the number of patients whose treatment was considered curative, significantly effective, or non‐effective, respectively Secondary outcomes: Not reported
Funding sources	No information provided
Declarations of interest	No information provided
Notes	Unit of randomisation: person Methods for including patients with bilateral disease: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Quote: "We randomly selected 160 patients who were diagnosed with chronic suppurative otitis media in outpatient department (male 92, female 58, age 16 to 65, mean 30). These patients were divided into rifampicin group (group A, 87 patients) and chloramphenicol group (group B, 73 patients). The two group showed no significant difference in terms of gender, age, and course of disease." Comment: it is not clear whether or not the patients were randomised
Allocation concealment (selection bias)	Unclear risk	Quote: "We randomly selected 160 patients who were diagnosed with chronic suppurative otitis media in outpatient department (male 92, female 58, age 16 to 65, mean 30). These patients were divided into rifampicin group (group A, 87 patients) and chloramphenicol group (group B, 73 patients). The two group showed no significant difference in terms of gender, age, and course of disease." Comment: not described
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: not mentioned. Given the different colour of the 2 different eye drops, blinding would be difficult to achieve.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Comment: not mentioned
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: attrition not reported. It seems that no participant was lost to follow‐up.
Selective reporting (reporting bias)	Unclear risk	Comment: a protocol for this trial is not available