Two thousand forty-seven (2047) ears of elementary school children of the Republic of Trinidad were screened with pure-tone and immitance tests. Approximately 20 percent of the ears showed type B and C tympanograms, compared with only 2 percent failing a 30 dB, 4 K Hz pure tone. In 13 percent an ipsilateral middle ear muscle reflex could not be elicited. Results are reported in terms of the subjects' racial background. This study tends to support the theory of a genetic origin of otitis media.
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