104 / 162
102 | Chapter 5
prediction (with a mean correlation coefficient of r = 0.94 over the whole array) was given by the T-level of
electrode 7, yielding the following prediction formula:
As shown in figure 5b, the neighboring electrodes in the center of the array provided comparable results,
ra ) was given by the T-level of e ectrode 7, yielding the
following prediction formula:
T-level
(
electrode
) = 0.01 (
electrode
2
– 7
2
) +
0.025 (
electrode
– 7) +
T-level
electrode
7
(
in dB
).
(2)
As shown in figure 5b, the neighboring electrodes in the
center of the array provided comparable results, while the
mean r was reduced at both ends of the array (to r = 0.86).
R-values for electrodes 2, 5, 9 and 14 are not shown in
figure 5b, since these electrodes were active in only less
than 33% of the subjects (table 3).
predicted T-levels versus the
electrode contacts, while tabl
numerical data. Again, it is cl
slightly better for the center r
cedure was repeated with a n
lections of 30% of the popu
same result.
To obtain a T-level profile
equation 2 can be reformulat
1 0 01
-
.
lectrod
T level lectrode
e
e
–18
El 13
El 14
El 15
El 9
El 10
El 11
El 5
El 6
El 7
El 1
El 2
El 3
–12 –6
–18 –12 –6
–18 –12 –6
Predicted T-level (dB)
Measrued T-level (dB)
0
–6
–12
–18
–6
–12
–18
–6
–12
–18
–6
–12
–18
c
Fig. 5.
c
Scatter plot of the measured T-levels vs. predicted T-levels for the rema
each electrode.
van der Beek/Briaire/Frijns
Audiol Neurotol 2015;20:1–16
DOI: 10.1159/000362779
8
–24
–18
ASM T-level (dB)
Word score (%)
–12
–6
0
R
2
linear = 0.117
0
20
40
60
80
100
a
ASM M-level (dB)
Word score (%)
6
–6
0
0
20
40
60
80
100
b
ASM DR (dB)
Word score (%)
6
12
18
0
0
20
40
60
80
100
c
R
2
linear = 0.109
ASV T-level (dB
2
)
Word score (%)
6
12
18
0
0
20
40
60
80
100
d
ASV M-level (dB
2
)
Word score (%)
6
0
0
20
40
60
80
100
e
ASV DR (dB
2
)
Word score (%)
6
0
0
20
40
60
80
100
f
Fig. 4.
Word scores vs. the ASM of the T-level (
a
), M-level (
b
) and DR (
c
) as well as vs. the ASV of the T-level
(
d
), M-level (
e
) and DR (
f
).
Downloadedby:
LeidenUniversity
145.88.209.33 - 11/23/20142:34:38PM
Fig. 4.
Word scores vs. the ASM of the T-level (a), M-level (b) and DR (c) as well as vs. the ASV of the T-l vel (d), M-level (e) and DR (f).