Please select the eligibility criteria that correspond to the clinical trial below.
Title: Effect of Adenotomy and Tympanostomy on Preventing Recurrent Otitis Media in the Young Children
Brief Summary: The purpose of this study is to find out if young children have more benefit of the combination of adenotomy and tympanostomy than plain tympanostomy in prevention of recurrent otitis media.


Options:
A: Inclusion criteria:

* Children aged 9-36 months.
* Children with at least one Greenlandic born parent with at least one Greenlandic born parent
* American Society of Anaesthesiologists physical status classification class 1 and 2
* B- or C2 - type curve measured by tympanometry at two visits three-four months apart or three episodes of acute otitis media in six months according to medical records or four episodes of acute otitis media in 12 months according to medical records
* Signed informed consent, signed by the legal guardian Exclusion criteria
* Children with orofacial cleft, Downs syndrome or known generalised immune deficiency
* American Society of Anaesthesiologists physical status classification class \> 2.
* Lack of signed informed consent, signed by the legal guardian.

Description of experimental and control intervention Experimental intervention: The intervention group will be treated with bilateral Donaldson ventilation tubes administered in general anaesthesia Control intervention: The control intervention is based on the current practice in Greenland, which includes systemic antibiotic treatment as well as aural toilette and topical antibiotics. Ventilation tube insertion during the study period is not accepted in the control group.

Children in the intervention group as well as the control group will be seen once a year by the visiting ear-nose-and throat (ENT)-specialist and have a final consultation after at least two years after randomisation.
B: Inclusion Criteria:

* history of mild ear ache or decreased hearing for three or more months, plus
* intact and immobile tympanic membrane by pneumatic otoscopy
* Type B tympanogram

Exclusion Criteria:

* any external ear condition that hampers visualization of tympanic membrane
* lost to follow up
C: Inclusion Criteria:

* Healthy, less than 62 days of age at enrollment

Exclusion Criteria:

* birth weight less than 5 lb (2268 g)
* small for gestational age
* history of neonatal asphyxia or other serious illness
* major congenital abnormality or chronic illness
* multiple birth
* sibling enrolled in the study
* in foster care or adopted before enrollment
* mother dead, seriously ill, a known drug or alcohol abuser before enrollment
* mother judged by study personnel to be too limited socially or intellectually to give informed consent or adhere to the study protocol
* mother less than 18 years of age
* English not the only household language
D: Inclusion Criteria:

* at least 3 otitis media episodes during the last half year
* address near (\< 50 km) the university hospital of Oulu

Exclusion Criteria:

* otitis media effusion lasting longer than two months without acute exacerbations
* prior adenoidectomy or tympanostomy
* head or neck malformation
* retarded child
* serious disease
* chemoprophylaxis for another disease

Answer: D