3. Summary of study characteristics.

Ref ID (no. participants)	Setting	Population	Intervention 1	Intervention 2	Treatment duration	Follow‐up	Background Treatment	Notes
Topical antibiotics versus placebo/no treatment (no background or aural toileting)
Kasemsuwan 1997 (n = 50)	Specialist hospital, Thailand	Mucopurulent otorrhoea with perforated tympanic membrane (CSOM)	Ciprofloxacin 250 mg/mL, 5 drops per 8 hours	Saline, 5 drops per 8 hours	1 week	1 week	Aural toilet on day 1, 4 and 7	Randomised by person
Topical antibiotic versus placebo/no treatment (systemic antibiotic as background treatment)
de Miguel 1999 (n = 50)	General hospital, Spain	Simple chronic otitis media (36%), osteitic chronic otitis media (25.6%), cholesteatomas chronic otitis media (13.6%), post surgery cases (24.8%)	Topical ciprofloxacin 0.2%, 3 drops per 8 hours and oral ciprofloxacin, 500 mg per 12 hours	No treatment	7 days	15 days	Aural toileting before beginning treatment, analgesics and antipyretics. Oral ciprofloxacin, 500 mg per 12 hours	Part of 5‐arm trial Randomised by person
Esposito 1990 (n = 40)	University clinic, Italy	Mild or moderate CSOM in acute stage	Ciprofloxacin 250 µg/mL, 3 drops per 12 hours	No treatment	5 to 10 days	2 weeks	Oral ciprofloxacin, 250mg per 12 hours	Part of 3‐arm trial Randomised by person
Mira 1993 (n = 50)	University clinic, Italy	Recurrence of CSOM or suppuration following mastoidectomy or tympanoplasty	Ceftizoxime 500 µg/mL, 2 x 2 mL washes per 12 hours	Saline, 2 x 2 mL washes per 12 hours	1 week	3 weeks	Systemic ceftizoxime by intramuscular route every 12 hours Aural toilet at first visit	Randomised by person
Ramos 2003 (n = 100)	ENT departments, Spain	Simple chronic otitis media (42.7%), chronic otitis media with osteolysis (19%), chronic cholesteatoma (14%), chronic otorrhoea in operated ears 24.3%)	Ciprofloxacin 0.2%, 0.5 mL per 8 hours	No treatment	1 week	10 days	Oral ciprofloxacin, 500 mg per 12 hours	Part of a 6‐arm trial Randomised by person
Quinolones versus aminoglycosides
Asmatullah 2014 (n = 134)	ENT department, Pakistan	Active tubotympanic type CSOM	Ofloxacin 0.3%, 12 drops per day	Gentamycin 0.3%, 12 drops per day	10 days	2 weeks	None mentioned	Randomised by person
Fradis 1997 (n = 40)	Outpatient clinic, Israel	Chronic otitis media	Ciprofloxacin (no conc), 15 drops per day	Tobramycin (no conc), 15 drops per day	3 weeks	3 weeks	None mentioned	Part of 3‐arm trial Randomised by ear
Kaygusuz 2002 (n = 40)	University ENT clinic, Turkey	CSOM	Ciprofloxacin 0.3%, 6 drops per day	Tobramycin 0.3%, 6 drops per day	3 weeks	3 weeks	Daily aspiration	Translated from Turkish Part of 4‐arm trial Randomised by person.
Nawasreh 2001 (n = 88)	Unclear setting, Jordan	CSOM and intermittent mucopurulent heavy discharge for more than 1 year	Ciprofloxacin 200 µg/mL (0.02%), 15 drops per day	Gentamicin 5 mg/mL, 15 drops per day	10 days	2 weeks	None mentioned	Randomised by person
Lorente 1995 (n = 308)	Hospital ENT clinics, Spain	CSOM (purulent discharge > 3 months and perforated membrane)	Ciprofloxacin 0.3%, 15 drops per day	Gentamycin 0.3%, 15 drops per day	8 days	30 days	Unclear	Translated from Spanish Assume this is same as Sabater paper Randomised by person
Tutkun 1995 (n = 44)	University hospital, Turkey	CSOM and purulent discharge for more than 1 year	Ciprofloxacin 200 µg/mL (0.02%), 15 drops per day	Gentamicin 5 mg/mL, 15 drops per day	10 days	10 days	None mentioned	Randomised by person
Jamalullah 2016 (n = 80)	Otolaryngology department, Pakistan	CSOM (tubotympanic type)	Ofloxacin 0.6%, 12 drops per day	Gentamycin 0.3%, 12 drops per day	2 weeks	2 weeks	One aural toilet at start	Randomised by person
Quinolones versus others
Siddique 2016 (n = 200)	Specialist hospital, Pakistan	Tubotympanic type of CSOM	Ciprofloxacin (no conc), 3 drops per 12 hours	Neomycin/polymixin/gramicidin‐D (no conc), 2 drops per 12 hours	Unclear (probably 4 weeks)	4 weeks	No information	Randomised by person
van Hasselt 1997 (n = 50)	Rural setting, Malawi	Children with CSOM	Ofloxacin 0.3%, 3 drops per 8 hours	Neomycin 0.5%/polymixin B 0.1%, 3 drops per 8 hours	2 weeks	2 weeks	Aural toilet at start and weekly	Part of a 3‐arm trial Only presented as an internal report Unclear unit of randomisation, results reported by ear
van Hasselt 1998a (n = unclear)	Rural setting, Malawi	"Mainly children" with CSOM	Ofloxacin 0.3%, 6 drops per 12 hours	Neomycin/polymixin B (no conc), 6 drops per 12 hours	2 weeks	8 weeks	Aural toilet at start and weekly	Only a presentation given at a conference available Unclear unit of randomisation, results presented by ear Part of 4‐arm trial ‐ once weekly arms have not been included.
Aminoglycosides versus trimethoprim, sulphacetamide and polymixin B (TSP)
Gyde 1978 (n = 91)	Outpatient clinic, Canada	Otitis externa (21%), CSOM (51%), subacute otitis (16%), postoperative infection (21%)	Trimethoprim, sulphacetamide and polymyxin B, 16 drops per day	Gentamicin 0.3%, 16 drops per day	Mean: 16 days	12 months	Not reported	Translated from French Randomised by person but reported by ear Semi cross‐over trial
Rifampicin versus chloramphenicol
Liu 2003 (n = 160)	Outpatient department, China	CSOM	Rifampicin 0.1%, 9 drops per day	Chloramphenicol 0.25%, 9 drops per day	2 weeks	2 weeks	3% hydrogen peroxide ear wash daily	Translated from Chinese Randomised by person

CSOM: chronic suppurative otitis media