In otitis media with effusion (secretory otitis media or glue ear), ventilation tubes (tympanostomy tubes, pressure equalisation tubes, or grommets) are placed in the eardrums to improve the hearing, behaviour, and development of children. This, the commonest operation in children worldwide has an evidence base which is periodically scrutinised.1 Guidelines attempt to foster stringent criteria for the operation because in most cases otitis media is mild and non-persistent, and the consequences of fluctuating hearing losses for language development have been exaggerated in the past.2 In the linked study (doi:10.1136/bmj.a1607) Keyhani and colleagues examined the clinical characteristics of children with otitis media in New York who had ventilation tubes and compared these with the recommendations of two sets of expert guidelines and a set of RAND appropriateness criteria.3 Agreement with recommendations was very low—only 30.3% of tympanostomies were concordant with the explicit criteria and only 7.5% were concordant with one of the …