D. Robles-Camarillo et al. / J. Biomedical Science and Engineering 6 (2013) 1-7 7
Table 5. Linear regression results for VA: Diagnosis type.
Group Linear model
r r2 StdError
RP VA = 0.0038 t + 0.4919 0.8915 0.9442 0.0251
Usher I VA = 0.0022 t + 0.2550 0.7602 0.8719 0.0236
Stimulated
Usher II VA = 0.0034 t + 0.5257 0.8384 0.9156 0.0281
RP VA = −0.0012 t + 0.6205 0.4674 0.6837 0.0233
Usher I VA = −0.0007 t + 0.3045 0.5167 0.7188 0.0134
Non stimulated
Usher II VA = −0.0004 t + 0.6053 0.0471 0.2170 0.0331
cient modeled, because their correlation coefficient (r)
and coefficient of determination (r2) are so close to 1
(Table 4), followed by the group of SE of patients be-
tween 31 and 50 years old, with the same characteristics
(Table 3). This means that the variability of measure-
ments (VA) is low enough to describe the statistical
modeled tendency, making the model accurate for statis-
tical validation.
With those estimations it is possible to affirm the
safety of the proposed TES waveform and parameters as
well as a partial effect of recovery and in some cases the
improvement of VA characteristics. It is more challenging
to prove the efficacy of treatment and establish methods
of comparison between similar treatments [3] in a disease
such as RP, due to the natural course of disease pro-
gression in these patients, it can be highly variable [3].
We acknowledge that our trial is small and most results
are not statistically significant, but in further proposed
protocols we will consider correcting the statistical va-
lidation.
5. ACKNOWLEDGEMENTS
The authors thank Prof. Domenica Petulla (Culver Academies, IN,
USA), for her writing assistance, to Consejo Nacional de Ciencia y
Tecnología (CONACyT, México), the Universidad Politécnica de Pa-
chuca (UPP, México), the Instituto Politécnico Nacional (IPN, México)
and “Hospital Dr. Luis Sánches Búlnes” (APEC, México) for their
support in this research.
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