Karlidag 2002.

Study characteristics
Methods	Unblinded, parallel‐group randomised controlled trial with 8 weeks of treatment and follow‐up For this review, we compared those who received antibiotics (alone) to those with no treatment. Data on steroids are relevant for a separate review in this suite (Mulvaney 2022a).
Participants	Setting: Single‐centre, conducted in Turkey between January and December 2001 Sample size: Number randomised: 62 participants Number completed: 62 participants Participant (baseline) characteristics: Age: Antibiotics group: mean 5.8 years (SD 2.47) Steroids and antibiotics group: mean 6.57 years (SD 3.17) Watchful waiting group: mean 4.58 years (SD 2.30) Gender: Antibiotics group: 13 males 7 females Steroids and antibiotics group: 14 males 6 females Watchful waiting group: 11 males 11 females Inclusion criteria: Aged 2 to 12 years. Diagnosed with otitis media with effusion based on: History: hearing loss, feeling of fullness in the ear, watching TV with a loud volume, apathy, comprehension and speech impairment Otoscopy: grey, dull or light pink eardrum with thickening, retraction or increased vascularity Rinne negativity on tuning fork test Conductive hearing loss Type B or C tympanogram Exclusion criteria: Previous insertion of ventilation tubes Allergy to ampicillin/sulbactam Antibiotic or nasal spray use in the past 2 weeks Immune disorders or systemic illnesses
Interventions	Antibiotic group (n = 20 randomised, n = 20 completed) Ampicillin/sulbactam 25 mg/kg/day, administered in 2 divided doses, orally for 8 weeks Steroids and antibiotics group (n = 20 randomised, n = 20 completed) Antibiotic as above, plus budesonide intranasal spray, 200 µg/day administered in 2 divided doses for 8 weeks No treatment group (n = 22 randomised, n = 22 completed) Active monitoring
Outcomes	Primary outcomes relevant to this review: Hearing Not reported Disease‐specific quality of life Not reported Adverse events Not reported Secondary outcomes relevant to this review: Presence/persistence of otitis media: proportion of ears with persistence of OME At 8 weeks
Funding sources	None reported
Declarations of interest	Not reported
Notes	Research integrity checklist No retractions or expressions of concerns were identified Prospective trial registration was not applicable, as this study was published before 2010 Limited information on baseline characteristics was presented, but no concerns were identified from the reported data Full follow‐up was reported, with no reasons given No implausible results were noted Different numbers were recruited to each group
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: participants were "randomly allocated" into 3 groups. No information on sequence generation.
Allocation concealment (selection bias)	Unclear risk	Comment: no details were provided on any methods used to conceal allocation.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Comment: participants were aware of their treatment allocation.
Blinding of outcome assessment (detection bias) All outcomes	High risk	This was an unblinded trial. We presume that the outcome assessors were also aware of treatment assignment.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: full follow‐up is reported.
Selective reporting (reporting bias)	Unclear risk	Comment: no protocol is available with which to compare the reported outcomes.
Other bias	High risk	Comment: follow‐up is inadequate to allow appropriate comparison of antibiotics and no intervention. Outcomes reported at this stage may be more likely to favour the active intervention, as insufficient time has elapsed to allow for spontaneous resolution.