G.A. Zielhuis

SCREENING FOR OTITIS MEDIA WITH EFFUSION IN PRESCHOOL CHILDREN

1439 Dutch children were included in a randomised trial to evaluate the efficacy of preschool screening for otitis media with effusion (OME) by 3-monthly tympanometry. Children with bilateral OME on two consecutive occasions were referred for further investigation and then, if parents gave their consent, allocated at random to treatment or non-treatment groups. The effect of childhood screening for OME and subsequent treatment was evaluated by assessment of language performance; no benefit was found, mainly because of the large degree of spontaneous recovery.

The effect of short-term ventilation tubes versus watchful waiting on hearing in young children with persistent otitis media with effusion: a randomized trial.

Objective To study the effect of short-term ventilation tubes in children aged 1 to 2 yr with screening-detected, bilateral otitis media with effusion (OME) persisting for 4 to 6 mo, as compared with watchful waiting. Design Multi-center randomized controlled trial (N = 187) with two treatment arms: short-term ventilation tubes versus watchful waiting. Young children underwent auditory screening; those with persistent (4 to 6 mo) bilateral OME were recruited. Results The mean duration of effusion over 1-yr follow-up was 142 days (36%) in the ventilation tube (VT) group versus 277 days (70%) in the watchful waiting (WW) group. After 6 mo of follow-up, the pure-tone average in the VT group was 5.6 dB A better than that in the WW group. After 12 mo, most of the advantage in the VT group had disappeared. After the insertion of ventilation tubes, the children with poorer hearing levels at randomization improved more than the children with better hearing levels. The largest difference in hearing levels was found between the children in the VT group whose ventilation tubes remained in situ and the children in the WW group. In the VT children with recurrence of OME, the hearing levels again increased, but remained slightly lower than those in the infants with persistent OME in the WW group. Conclusions Ventilation tubes have a beneficial effect on hearing in the short run (6 mo); this effect, however, largely disappears in the long run (12 mo). This is probably due to partial recurrent OME in the VT group and to partial spontaneous recovery in the WW group.

An epidemiological approach to the etiology of middle ear disease in The Netherlands

SummaryThe etiology of middle ear disease in Nijmegen, The Netherlands was studied on the basis of a data set collected in a prospective epidemiological study on otitis media with effusion (OME) in a cohort of 1439 preschool children. A factor analysis was used to evaluate two hypotheses: (1) that OME, acute otitis media (AOM), common cold and tonsillitis are manifestations of the same pathological entity, and (2) that a group of children can be distinguished who develop these conditions more frequently than average. The results only partly supported these hypotheses. The correlation between OME, AOM, common cold and tonsillitis was lower than expected from a review of the literature. Common cold appeared to be the ubiquitous ENT disease in childhood and, depending on the childs predisposition, could be accompanied by OME, AOM or tonsillitis. The course of middle ear and upper airway disease showed a gradual scale from “healthy” to “ill” with most of the children suffering from these conditions at an average frequency.

Bayes' theorem: A negative example of a RCT on grommets in children with glue ear

Bayesian inference presupposes that practitioners’ belief in the effectiveness of medical intervention is the product of prior belief and recent evidence from studies. Although increasingly used, up to now the posterior belief calculated according to the theorem has not been compared with an empirically measured posterior belief. We conducted a RCT, which was preceded by elicitation of prior beliefs among ENT-surgeons, and which was followed by elicitation of posterior beliefs among ENT-surgeons, 1 year after completion of the trial. We compared the posterior beliefs of ENT-surgeons about the effect of grommets in children with glue ears, as predicted by Bayes’ theorem with actual measured posterior beliefs. The distribution of the measured posterior beliefs was not in line with the calculated posterior, but almost identical to the distribution of the measured prior beliefs. The results showed that our trial had little or no impact on the beliefs of the ENT-surgeons, i.e. they did not adjust their belief to the extent that was expected according to Bayes’ theorem.