The repeatability of corticomotor threshold measurements

dc.contributor.author	Kimiskidis, VK	en
dc.contributor.author	Papagiannopoulos, S	en
dc.contributor.author	Sotirakoglou, K	en
dc.contributor.author	Kazis, DA	en
dc.contributor.author	Dimopoulos, G	en
dc.contributor.author	Kazis, A	en
dc.contributor.author	Mills, KR	en
dc.date.accessioned	2014-06-06T06:46:10Z
dc.date.available	2014-06-06T06:46:10Z
dc.date.issued	2004	en
dc.identifier.issn	09877053	en
dc.identifier.uri	http://dx.doi.org/10.1016/j.neucli.2004.10.002	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/2815
dc.subject	Corticomotor threshold	en
dc.subject	Repeatability	en
dc.subject	Transcranial magnetic stimulation	en
dc.subject.other	adolescent	en
dc.subject.other	adult	en
dc.subject.other	aged	en
dc.subject.other	analysis of variance	en
dc.subject.other	analytic method	en
dc.subject.other	article	en
dc.subject.other	confidence interval	en
dc.subject.other	corticomotor threshold	en
dc.subject.other	female	en
dc.subject.other	hemisphere	en
dc.subject.other	human	en
dc.subject.other	human experiment	en
dc.subject.other	male	en
dc.subject.other	maximum allowable concentration	en
dc.subject.other	measurement	en
dc.subject.other	motor cortex	en
dc.subject.other	nervous system parameters	en
dc.subject.other	normal human	en
dc.subject.other	probability	en
dc.subject.other	reproducibility	en
dc.subject.other	scalp	en
dc.subject.other	school child	en
dc.subject.other	statistical significance	en
dc.subject.other	stimulation	en
dc.subject.other	time	en
dc.subject.other	Adolescent	en
dc.subject.other	Adult	en
dc.subject.other	Aged	en
dc.subject.other	Child	en
dc.subject.other	Electromyography	en
dc.subject.other	Female	en
dc.subject.other	Hand	en
dc.subject.other	Humans	en
dc.subject.other	Magnetics	en
dc.subject.other	Male	en
dc.subject.other	Middle Aged	en
dc.subject.other	Motor Cortex	en
dc.subject.other	Muscle Relaxation	en
dc.subject.other	Neurophysiology	en
dc.subject.other	Reference Values	en
dc.subject.other	Reproducibility of Results	en
dc.title	The repeatability of corticomotor threshold measurements	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.neucli.2004.10.002	en
heal.publicationDate	2004	en
heal.abstract	Threshold (Th) is a neurophysiological parameter frequently used in TMS studies. The present study was designed to investigate the repeatability of the Th measurements by reexamining healthy subjects over various time points. Overall, 82 subjects (median age: 19 years, range: 12-65) entered the study. Following a baseline examination, there were six retest sessions: S0 (n = 8 hemispheres reexamined, mean interval x = 19 min), S1 (n = 34 hemispheres reexamined, mean interval x = 4 days), S2 (n = 32 hemispheres, x = 29 days), S3 (n = 30 hemispheres, x = 106 days), S4 (n = 30 hemispheres, x = 183 days) and S5 (n = 30 hemispheres, x = 1867 days). Stimulation was performed with a figure of eight coil and Th was defined at 1% steps. At baseline, controls had an MT of 41.1 ± 8. Mean difference of MT from baseline was 0.62 on S0 (95% confidence interval (CI) of the difference: -1.04 to +2.29), 0.13 on S1 (95% CI: -1.2 to +1.5), -0.03 on S2 (95% CI: -1.1 to +1.06), -2.07 on S3 (95% CI: -4.33 to +0.19), 0.15 on S4 (95% CI: -0.98 to +1.28) and 0.87 on S5 (95% CI: -0.49 to +2.23). None of these differences were statistically significant (repeated measures ANOVA, P > 0.05). The upper limit of MT difference that an individual subject might have with a probability of 95% (measurement error) was 8. The repeatability of the method was found to be independent from the age of the subjects, the magnitude of threshold or the test-retest interval. The topography of corticomotor threshold was also investigated. Minimal threshold values were obtained from a restricted area of scalp sites that always included the fixed stimulation point of the current protocol. Therefore, using a fixed stimulation point is an adequate technique for measuring threshold. In conclusion, threshold is a stable parameter on an individual and group basis. These data quantify the repeatability of the method and may prove useful in the interpretation of findings during longitudinal studies. © 2004 Elsevier SAS. All rights reserved.	en
heal.journalName	Neurophysiologie Clinique	en
dc.identifier.issue	6	en
dc.identifier.volume	34	en
dc.identifier.doi	10.1016/j.neucli.2004.10.002	en
dc.identifier.spage	259	en
dc.identifier.epage	266	en