Table 1—

Correlation and agreement (according to the method of Bland and Altman) between the point-of-care and conventional nerve conduction studies in the 72 subjects with diabetes

ParameterSpearman correlation coefficientSystematic bias*
Mean bias95% CI (in units of measurement)95% CI (percentage of conventional nerve conduction value)
Median
    Motor latency0.830.36 ms−0.26 to 0.98 ms−8 to 28%
    Motor F-wave latency0.760.29 ms−5.24 to 5.82 ms−22 to 20%
    Sensory amplitude0.90−5.89 μV−25.16 to 13.37 μV−62 to 5%
    Sensory latency0.830.43 ms−0.75 to 1.61 ms−5 to 34%
Peroneal
    Motor amplitude0.83−1.16 mV−4.50 to 2.19 mV−85 to 43%
    Motor latency0.83−0.42 ms−2.02 to 1.19 ms−30 to 17%
    Motor F-wave latency0.860.74 ms−6.55 to 8.02 ms−18 to 11%
Sural
    Sensory amplitude0.91−1.55 μV−5.41 to 2.31 μV−100 to 33%
    Sensory latency0.87−0.93 ms−1.63 to −0.22 ms−31 to −8%
  • All parameters are measured at the distal point of the limb. Data for median motor distal amplitude measurements not included owing to the technical limitations of the point-of-care system for measuring this parameter (see research design and methods).

  • *

    * Bias is calculated as a point-of-care nerve conduction value − conventional nerve conduction value.

  • All Spearman coefficients have P < 0.0001.