One thousand six hundred and eighty-eight children undergoing myringotomy w
ere studied to determine the rate of 'dry taps' and factors associated with
a dry middle ear at operation. The percentage of bilateral dry taps was 16
%. The dry tap rate was significantly higher in the following groups: older
children, those with an A, C1 or C2 tympanogram at the time of listing, mi
lder hearing loss, a preceding history of recurrent acute otitis media and
operation performed during the summer or autumn. There was no significant r
elationship between the dry tap rate and the time on the waiting list, the
gender of the child or the order in which right or left myringotomies were
performed. Careful preoperative reassessment of any child with a type A, C1
or C2 tympanogram should be made to prevent unnecessary surgery. Separatin
g those listed for treatment of recurrent acute otitis media from those wit
h OME would prevent these being included in the overall dry tap rate.