Mira 1993.

Methods	Two‐arm, single‐blinded, parallel‐group RCT, with 7 days duration of treatment and 21 days follow‐up
Participants	Location: Italy, 1 site Setting of recruitment and treatment: Department of Otolaryngology, published in 1993 Sample size: 248 Number randomised: 128 in intervention, 120 in comparison Number completed: 127 in intervention, 120 in comparison Participant (baseline) characteristics: Age: mean 42.6 ± 13.7 (range 14 to 79) Gender (F/M): 124 (50%)/124 (50%) Main diagnosis: recurrence of chronic suppurative otitis media or suppuration following mastoidectomy or tympanoplasty 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: Confirmation of perforated tympanic membrane: unclear Presence of mucopurulent discharge: unclear Duration of symptoms (discharge): not reported Other important effect modifiers: Alternative diagnosis of ear discharge: Suppuration following tympanoplasty: 26/248 (10.5%) Suppuration following mastoidectomy: 26/248 (10.5%) Number who have previously had grommets inserted: not reported Number who have had previous ear surgery: at least 52/248 (21%) Number who had previous antibiotic treatment for CSOM: not reported Inclusion criteria: Age ≥ 14 years Recurrence of chronic suppurative otitis media or suppuration following mastoidectomy or tympanoplasty Exclusion criteria: Ascertained or suspected hypersensitivity to cephalosporins and/or penicillins External otitis Cholesteatoma Concomitant serious diseases (neoplasias, renal or hepatic insufficiency)
Interventions	Intervention (n = 128): ceftizoxime 2 g dissolved in 4 mL of saline twice per day for 7 days. Method of administration: 2 mL of solution was instilled into the auditory canal while the patient was supine and keeping their head turned to one side. The patient remained in this position for 3 to 5 minutes, after which they released the excess liquid by turning their head to the opposite side. The remaining part of the supplied solution was then also instilled and the canal was padded with an ear gauze. Morning treatment: ear pad was removed after 2 hours Evening treatment: ear pad kept in situ overnight and removed the next morning Comparator group (n = 120): saline solution – same method as per intervention arm above Concurrent treatment: at the first visit a specialist aspirated local secretions All patients received systemic antibiotics 2 g daily of ceftizoxime by intramuscular route (1 vial every 12 hours) for 7 days
Outcomes	Ear discharge was reported but not in a way that we could use in this review
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)	Unclear risk	Quote: "The study was a single‐blind randomised investigation." Comment: there is no information about the method of sequence generation
Allocation concealment (selection bias)	Unclear risk	Comment: there is no information regarding allocation concealment. It is not clear whether the healthcare professionals could have influenced the allocation to treatment group
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Quote: "The study was a single‐blind randomised investigation." Comment: although the study indicates that the study was "single‐blinded" it does not provide details of who was blinded to treatment. It is assumed that it was the participants who were blinded to treatment. The saline placebo was used at the same volume and with the same method of application as the antibiotic ear drops.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "The study was a single‐blind randomised investigation." Comment: it is assumed that the single blinding was blinding of the participants. In this case the outcome assessors would have known the treatment to which the participants were allocated when assessing outcomes. This could have led to bias.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: it appears that only 1 participant in the topical antibiotics group did not complete the trial (1/128; 0.7%)
Selective reporting (reporting bias)	High risk	Comment: a protocol was not available through clinicaltrials.gov or the European Clinical Trials Registry. The outcomes as reported in the methods section are not all well presented in the results section. The methods sections reports some information about the scales used to measure symptom scores but it is not clear which symptoms were measured. Similarly the methods section gives definitions of the outcomes 'recovered', 'improved' and 'unchanged or worsened' but these are not presented in the results. The results are given descriptively without any information about precision.