title: Test-retest reliability of contact heat-evoked potentials from cervical dermatomes.
abstract: The purpose of this study was to investigate the test-retest reliability of contact heat-evoked potentials (CHEPs) in neurologically healthy subjects from cervical dermatomes (C4-C8). Seventeen individuals underwent test-retest examination of cervical CHEPs. Peak latencies and peak-to-peak amplitude of N2-P2 and ratings of perceived intensity were analyzed using test-retest reliability statistics (intraclass correlation coefficients [ICCs] and Bland-Altman confidence parameters). For comparison, a group of similar age and gender was also examined with dermatomal somatosensory-evoked potentials (dSSEPs, n = 17). The ICC values for CHEP latency and amplitude parameters were significant (P < 0.05) and corresponded to at least "fair" reliability, while peak-to-peak amplitude demonstrated "substantial" (≥0.81) reliability for all dermatomes. The coefficients of repeatability (i.e., 2SD of the difference between examinations) confirm that CHEPs and dSSEPs are reliable according to measures of latency. Superior peak-to-peak amplitude test-retest reliability was found for CHEPs. In conclusion, the test-retest reliability of dSSEP and CHEP parameters supports the fact that these outcomes can be used to objectively track changes in spinal conduction in the dorsal column and spinothalamic tract, respectively. The reliable acquisition of CHEPs may depend on the intensity of the sensation reported by the subject for a given area of skin stimulated.
authors.affiliation: International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, Canada. jkramer@paralab.balgrist.ch
authors.forename: John L K
authors.initials: JL
authors.lastname: Kramer
authors.forename: Philippa
authors.initials: P
authors.lastname: Taylor
authors.forename: Jenny
authors.initials: J
authors.lastname: Haefeli
authors.forename: Julia
authors.initials: J
authors.lastname: Blum
authors.forename: Jose
authors.initials: J
authors.lastname: Zariffa
authors.forename: Armin
authors.initials: A
authors.lastname: Curt
authors.forename: John
authors.initials: J
authors.lastname: Steeves
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D005073:Evoked Potentials, Somatosensory / Q000502:physiology*; D005260:Female; D006358:Hot Temperature; D006801:Humans; D008297:Male; D011930:Reaction Time / Q000502:physiology; D015203:Reproducibility of Results; D012867:Skin / Q000294:innervation*