Gardner Robertson (GR) scale and frequency?

[larryw]

Many studies I have read refer to the Gardner Robertson (GR) scale (from Grade I good-excellent to Grade IV poor and Grade V none), but I can't see anything saying at what frequency they measure this. If I look at my audiology results for the affected ear, I would be Grade I at 1500 hz but drop to Grade II at 3000 and Grade III at 4000. (My "good" ear drops off markedly between 3000 and 4000 as well).

I'm sure there is an obvious answer somewhere, but I just can't find it.

Thanks in advance, Larry

[PaulW]

Gardner Robertson scale is the average of four frequencies.
These frequencies are 0.5KHz 1KHz 2Khz 3KHz
So if your average across all 4 frequencies is -30db or better and your speech descrimination is 70% or better you are GR1.

The Gardner Robertson Scale is critisized as if your hearing is worse than -20db you may already have some challenges in a crowd.
It also leaves out 4KHz which is important for understanding speech, especially "S" and "F" and its a frequency most damaged by surgery and radiation