On otological examination all of the following will have positive fistula test except:

(a) Dead ear(Ref. Shambaugh, 6th ed., page 181)If there is a fistula on the medial wall but inner ear is dead (not responding to pressure changes), then in spite of presence of fistula, fistula test will be negative. This is false negative fistula test.If the footplate of stapes is hypermobile, it results in false positive fistula test.Fenestration operation is an iatrogenic cause of positive fistula test.