Fistula test is interpreted as Positive when on performing the test the patient develops nystagmus with fast component towards the test ear during application of pressure. (Pressure should be applied and kept there for upto 30 secs to see for nystagmus).
When no nystagmus occurs then it is a negative fistula test.
When the pressure is withdrawn, fast component in a positive test develops to the opposite side.
Presence of fistula test denotes a dehiscent sem circular canal, (most commonly lateral).
False positive is present in congenital syphilis (excessive mobility of stapes footplate).
False negative is present in dead labyrinth.