Rounding Results - Interacoustics OtoRead Instructions For Use Manual

OtoRead™ Instructions for Use - US Page 25

Rounding results

The user needs to be aware that the SNR and single PASS criteria are calculated from the full internal
precision of the instrument, and not from the values shown in the printout for the emission (TE) and noise
floor (NF) estimates.
This approach is used to preserve the full precision of the test results, but can result in some apparent errors
in the printout due to the effects of rounding.
Example: We assume the actual values at 1.5 kHz were TE = 4.5 dB, NF = -0.4 dB, which results in SNR =
4.9 dB. The printout values are rounded up to the nearest integer and are shown as TE = 5, NF = 0, and
SNR = 5. This can result in what appears to be an error with regard to the pass criterion.
Please note: If the pass criterion is 5 dB while the actual SNR = 4.9, the printed value will be 5, but a P will
NOT be printed.
Again, the pass/refer criterion is based on the full precision of the results, and not the rounded values that
are printed. The full precision value for the SNR must be equal to or greater than the pass criterion (5 dB in
this example) for the P to be printed. A similar apparent problem can occur where the printed SNR value
appears to be incorrect. If the actual values were TE = 4.5 dB, NF = 0.4 dB, resulting in SNR = 4.1 dB, the
printed values would be TE = 5 dB, NF = 0, SNR = 4. The printed SN value of 4 dB appears to be an error,
but is in fact correct.