ObjectiveIdentify the risk factors for otitis media with effusion (OME), especially laryngopharyngeal reflux (LPR), adenoid hypertrophy and allergic rhinitis, that could be used to develop prevention strategies in children.DesignA comparative cross-sectional study was conducted to make sure the adequacy of proportions of OME and non-OME cases in finding the related factors.SettingHistory taking, ear/nose/throat (ENT) examination, and tympanometry were performed in preschool and elementary schools. Flexible fibreoptic nasopharyngolaryngoscopy was performed in a bronchoesophagology outpatient clinic in a tertiary referral hospital in Jakarta, Indonesia.ParticipantsPreschool and elementary children in East Jakarta, Indonesia were recruited for this study. A total of 2016 participants underwent history taking, ENT examination and tympanometry. The case group was 46 children with OME, and the control group was 46 children without OME. The number of subjects fulfilled the minimum sample size for two proportions comparison.Main outcome measuresA type B tympanogram indicated OME. A Reflux Finding Score of more than 7 indicated LPR. Adenoid hypertrophy was diagnosed using flexible fibreoptic nasopharyngolaryngoscopy. Allergic rhinitis was diagnosed using a questionnaire based on the International Study of Asthma and Allergies in Childhood phase III that has been validated for Indonesians.ResultsThe proportion of LPR in the OME group was significantly higher than in the non-OME group, at 78.3% and 52.2%. The probability of OME occurrence in patients with LPR was 3.3 times higher than in patients without LPR (OR 3.3; 95% CI 1.33 to 8.189; p=0.01). There was no significant relationship between adenoid hypertrophy and OME (p=0.211; 95% CI 0.71 to 3.97), and also between allergic rhinitis and OME (p=0.463; 95% CI 0.61 to 4.28).ConclusionThe probability of OME occurrence in patients with LPR was 3.3 times higher than in patients without LPR. LPR should be considered in patients with OME and vice versa.