Background: The diagnosis of otitis media with effusion (OME) is difficult using only medical history and otoscopy. Tympanometry may, therefore, be helpful in the diagnosis and follow-up of OME in general practice. Studies regarding the reliability of tympanogram production and validation of tympanogram outcome have been performed.
Objective: To gain insight into the usability of microtympanometry and the degree of agreement and accuracy of tympanogram classification in general practice.
Methods: Data were collected in the offices of 49 general practitioners (GP's). The usability of the microtymp was monitored against a checklist. GP's (39) classified 47 tympanograms according to Jerger's modified classification, designating them as 'OME', 'no OME' or 'interpretion impossible'. The gold standard was the consensus over the 47 tympanograms reached by three doctors very experienced in tympanometry.
Results: Of the general practitioners, 61% handled the microtymp faultlessly. The overall inter-observer agreement was moderate to substantial; with respect to the gold standard 74% of the general practitioners had a satisfactory to almost perfect agreement. These results were achieved after instruction and training; longer practice produced no significant improvement in the agreement.
Conclusion: After training and instruction microtympanometry is a reliable diagnostic instrument in general practice. The classification of tympanograms is satisfactory. Classification problems arise when the curve is not a good one. Additional criteria for the assessment of the curves are proposed.