Spectral gradient acoustic reflectometry compared with tympanometry in diagnosing middle ear effusion in children aged 6 to 24 months.

OBJECTIVES To evaluate the accuracy of spectral gradient acoustic reflectometry (SGAR) in children aged 6 to 24 months, and to compare SGAR with tympanometry. DESIGN Comparison of diagnostic tests. SETTING Inner-city primary care center in Pittsburgh, Pennsylvania. PARTICIPANTS A total of 786 healthy children aged 6 to 24 months. MAIN OUTCOME MEASURES Test characteristics of SGAR (sensitivity, specificity, and positive and negative predictive values) and receiver operating characteristic curves from the SGAR and tympanometric data. RESULTS The SGAR results were available for 3096 otoscopic examinations in 647 children. Tympanometric results were available for 2854 otoscopic examinations in 597 children. Using the recommended SGAR pass or fail cutoff, 53% of the ears in which effusion was present would have been considered effusion free (sensitivity, 47%). Only 10% of the ears without effusion would have been considered to have effusion (specificity, 90%). The area under the receiver operating characteristic curve was 0.78 for SGAR and 0.83 for tympanometry. CONCLUSION Spectral gradient acoustic reflectometry is slightly less discerning than tympanometry in predicting the presence or absence of middle ear effusion in children younger than 2 years.