ETS Form 1 Practice Exam

Impedance/immittance screening relies on how the tympanic membrane and middle ear respond to pressure changes. That response can be temporarily altered by illnesses that affect the ear, such as a cold or an ear infection, which may bring fluid into the middle ear or cause eustachian tube congestion. When these temporary conditions are present, the tympanic membrane may not move normally, leading to an abnormal result that doesn’t reflect the true, longer-term status of the middle ear. Waiting 3–5 weeks allows those temporary factors to resolve, so a retest is more likely to reveal the genuine middle-ear function rather than a result driven by a transient illness. The other options don’t address why waiting improves accuracy: room acoustics or a specific test frequency aren’t about the need to delay re-testing, and while retesting immediately can be unreliable in the sense of being affected by current illness, the key reason is that temporary conditions may resolve, clarifying the true status.