4KHz bone conduction test worthwhile?

For years I have been force by the (now defunct) UK Hearing Aid Council to perform b/c tests up to 4KHz.

However I have never trusted tests at the 4 KHz point … and Google searches show the same doubts elsewhere.

However in the UK since the 1st April 2010 we operate on a ‘best practice’ basis.

Sooooo … should / could I safely give up testing that pesky 4KHz b/c frequency?

I’d say yes, even though it is best practice here in the states as well.

dr. amy

How do you do the bone conduction test? I hate that test with my audie, because it always heels like the contraption she’s putting on my head is going to snap off any second and go flying across the room.

No, you can’t give it up, it’s part of the BSA standard. It’s especially useful in determining Cahart’s Notch and if your work is ever called in as evidence of noise damage, you want to be able to prove that the 4KHz is entirely SN or it may affect the size of the possible claim.

I agree that it doesn’t always seem to coincide properly with the loss, but there’s also calibration issue in the reading of the standard that has caused a few issues.

Hmm … I’m not sure that I’m still bound by the BSA standard.

The HAC connection to that standard seemed a bit informal - and nothing I’ve seen in the HPC paperwork mentions it.

For example, I could adopt another standard from say the USA … or even create my own, based on research papers etc!

As long as the the test procedure was ‘best practice’, I should be OK.

You could adopt another standard if you wanted, but why would you - doing the 4KHz doesn’t take that long. Or is it the masking that’s slowing you down?

Obviously for pension cases or cases in which some one else is depending on the info in the audio workup (court cases), you’d want to include bone at 4K. But for hearing aid evals, unless you suspect collapsing canals, it’s not going to provide additional info. Research shows it’s unreliablity, and i cant think of any pathology that has a conductive component only at 4K and doesnt show up at other frequencies.

dr. amy

Ossicular chain discontinuity?

I’d go with that, or Otosclerosis.

or even collapsible ear canals if not using insert earphones, but i’ve seen reliability issues in both those cases as well. Tympanometry can give that info as well or better than bone at 4kHz.

dr. amy

and you’d usually see that with bone at 2Khz as well

dr. amy