Fiabilidad test-retest del umbral de sensibilidad a la vibración periférica en los pacientes con dolor crónico de espalda baja

Abstract

IntroductionChronic non-specific low back pain could cause loss of peripheral sensitivity. This study has aimed to determine relative and absolute test-retest reliability of the «Two alternative Forced Choice» protocol as a method of estimating the peripheral vibration sensitivity threshold (PVST). Material and methodsSix patients with chronic non-specific low back pain were referred from a hospital unit specialized in patients with pain. The study used the Vibratron II® device (Sensortek, Inc. Clifton, NJ, EE. UU.) to assess PVST on two occasions separated by a 12-week time period. The procedure was carried out in accordance with the supplier's instructions. The PVST was also calculated using different robust estimators of location. The data were analyzed by calculating the relative reliability indices, intra-class (ICC) and absolute correlation coefficients, standard error of measurement and smallest real difference (SRD). The data was represented using the corresponding Bland-Altman plots. ResultsThe reliability indices obtained in this study showed high relative correlation (ICC>0.80). The absolute statistics showed that reliability was moderate (SEM <0.90 vibration units; SRD<2.60). ConclusionThe procedure used for determining PVST showed values a high temporal consistency. Thus, it could be used as a measure to assess changes in peripheral sensitivity of patients with chronic non-specific low back, especially in homogeneous samples in terms of PVST.