title: Intraindividual Variability and Long-Term Changes of Thermal Quantitative Sensory Testing.
abstract: Thermal threshold examinations are widely used in the clinical setting and in studies to assess the function of the peripheral sensory nervous system. Little is known about the variation from one side of the body to the other and the long-term temporal changes and variability. In this study, 134 healthy subjects were stimulated at the dorsum of the hand, lower arm, upper arm, thorax, abdomen, thigh, lower leg, and dorsum of the foot bilaterally to determine the cold detection threshold and the warmth detection threshold. Forty-eight subjects were reexamined after 2 weeks and 26 weeks at the hand and foot. Bilateral stimulations resulted in relative intertrial variations ranging from 19% to 40%. There was no significant temporal change for repeated measures. Analysis of the individual measurements of each subject at baseline and at 26 weeks, however, resulted in relatively large intertrial variations of 19% to 42%. Sample sizes ranging from 42 to 76 subjects in each group would be required to detect a minimal relevant difference of the magnitude of the 95 percentile of the absolute changes. Attention should be given to the relatively large intraindividual variation when used as a tool for diagnosis or monitoring in the clinical setting. Cold and warmth detection threshold are well suited as outcome measures in longitudinal studies.
authors.affiliation: Department of Neurology, Odense University Hospital; and Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Krøigård
authors.forename: Isaivani
authors.initials: I
authors.lastname: Sothynathan
authors.forename: Søren H
authors.initials: SH
authors.lastname: Sindrup
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005528:Foot / Q000294:innervation; D006225:Hand / Q000294:innervation; D006801:Humans; D007206:Individuality; D008297:Male; D008875:Middle Aged; D012684:Sensory Thresholds / Q000502:physiology*; D013697:Thermosensing / Q000502:physiology*; D055815:Young Adult