Table 3. Normative tympanometric width data at 226 Hz from three studies. Tympanometric width is the pressure interval corresponding to a 50% reduction in peak compensated admittance.

Study Population Pressure

rate
Ear-canal

correction
M 90%

range
deJonge

(1986)
Adults 50 daPa/s −300 daPa 110 60–160
Koebsell &

Margolis

(1986)
Children

(3–5 yrs)
50 & 200

daPa/s
Minimum 133 80–200
Margolis &

Heller

(1987)
Children

(3–5 yrs)
200 & 400

daPa/s
+200 daPa 100 59–151
Adults 200 & 400

daPa/s
+200 daPa 77 51–114