title: Reliability of the nociceptive blink reflex evoked by electrical stimulation of the trigeminal nerve in humans.
abstract: OBJECTIVE
  The nociceptive blink reflex (nBR) can be useful to investigate trigeminal nociceptive function. The aim of this study was to estimate the reliability of the nBR evoked by electrical stimulation of the three branches of the trigeminal nerve under the following conditions: over time (test-retest and intrarater reliability) and by two examiners (interrater reliability).
  
  
  METHODS
  Twenty-one healthy participants were evaluated in two sessions (24 h apart). The nBR was elicited by a so-called "nociceptive-specific" electrode placed over the entry zone of the right supraorbital (V1R), infraorbital (V2R), mental (V3R), and left infraorbital (V2L) nerve. The outcomes were individual electrical sensory (I0) and pain thresholds (IP); root mean square (RMS), area-under-the-curve (AUC), and onset latencies of R2 responses (determined twice after a recalibration session); and stimulus-evoked pain on a 0-10 numerical rating scale. Intraclass correlation coefficients (ICCs) and Kappa statistics were computed (α = 5%).
  
  
  RESULTS
  ICCs were fair to excellent in 82% of the psychophysical measures (fair 21%, good 31%, excellent 30%) and in 86% of V1R, V2R, and V2L nBR parameters, whereas 52% of V3R showed poor reliability. ICCs for intrarater reliability were fair to good in 70% of measurements (fair 20%, good 50%) and in 75% of interrater measurements after the recalibration (fair 55%, good 20%). All kappa values showed at least fair agreement and the majority of the nBR measures (93%) presented moderate to excellent reliability.
  
  
  CONCLUSIONS
  The nBR and its associated psychophysical measures can be considered a sufficiently reliable test.
  
  
  CONCLUSIONS
  The nBR can be recommended as an electrophysiological technique to assess trigeminal nociceptive function.
authors.affiliation: Section of Head and Face Physiology, Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Al. Octávio Pinheiro Brisola, 9-75, Bauru, CEP 17012-901, Brazil. yurimartinscosta@yahoo.com.br.|Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark. yurimartinscosta@yahoo.com.br.
authors.forename: Yuri Martins
authors.initials: YM
authors.lastname: Costa
authors.affiliation: Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark.|Section of Orofacial Pain and Jaw Function, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark.
authors.forename: Lene
authors.initials: L
authors.lastname: Baad-Hansen
authors.affiliation: Section of Head and Face Physiology, Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Al. Octávio Pinheiro Brisola, 9-75, Bauru, CEP 17012-901, Brazil.
authors.forename: Leonardo Rigoldi
authors.initials: LR
authors.lastname: Bonjardim
authors.affiliation: Department of Prosthodontics, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil.
authors.forename: Paulo César Rodrigues
authors.initials: PCR
authors.lastname: Conti
authors.affiliation: Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark.|Section of Orofacial Pain and Jaw Function, Department of Dentistry and Oral Health, Aarhus University, Aarhus, Denmark.|Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Svensson
mesh_terms: D000328:Adult; D001767:Blinking / Q000502:physiology*; D004558:Electric Stimulation; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D010146:Pain / Q000503:physiopathology*; D010147:Pain Measurement; D017288:Pain Threshold; D012018:Reflex / Q000502:physiology*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D014276:Trigeminal Nerve / Q000502:physiology*
keywords: Intraclass correlation coefficient; Nociceptive blink reflex; Reliability; Trigeminal nerve