Visual Tools For Counseling And Verification; Percentile Analysis - Interacoustics Affinity 2.0 Additional Information

2.0
Affinity Additional Information

2.12 Visual Tools for Counseling and Verification

2.12.1 Percentile Analysis

The Percentile Analysis can be added in the REM440 setup (see section 0.1)
The Percentile Analysis is implemented according to the IEC 60118-15 standard.
th
By default the 30th, 65
analysis of 100 measurements.
The 30th percentile (indicated in blue shading) is the sound pressure level below which 30% of the
measured levels are found for each frequency. The remaining 70% of the measured sound pressure levels
are higher. The 30th percentile thereby represents the lower valleys or the soft components of the speech
signal. This helps you ensure that even the soft valleys are above thresholds.
The 99th percentile (indicated in green shading) is the sound pressure level below which 99% of the
measured levels are found for each frequency. The 99th percentile may be interpreted as a peak indicator
which helps to ensure that no peaks come too close to the MPO and/or UCL's. In other words the 99
percentile represents the loud components of the speech signal.
Together the 30th and 99th percentile provides an "area of audibility". The 65th percentile serves as a
borderline between the 30th and 99th percentiles and is visually represented at the point where the blue and
green areas meet. The 65
the FFT analysis of the 100 measurements.
Picture note: On this illustration the percentile analysis reveals important information about the hearing aid
fitting. At 3-4 kHz the peaks of the signal (the 99
that even though we cannot fit above thresholds the client is still getting some speech information in this
frequency area since the 99
though the curve is above threshold and we match target, the lower valleys (30
thresholds and the client is thereby missing information.
, and 99th percentile are selected. These percentiles are calculated based on an FFT
th
percentile represents the median whereas the measurement is the average of
th
percentile is above thresholds. In the low frequency area we can see that even
th
percentile) are too close to the UCL. However, we also see
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th
th
percentile) are not above