Estudo da confiabilidade e validade de um hidropletismômetro para medida de edema no tornozelo

Abstract

Introduction: Reliable and valid measurement instruments for the quantification of the ankle/foot volume are very important to evaluate the effectiveness of the rehabilitation techniques in reducing edema. Objective: To evaluate the reliability and the validity of the water plethysmographer, a measurement instrument for the ankle/foot volume, developed by the Departments of Physiotherapy and Mechanical Engineering of the Universidade Federal de Minas Gerais, Brazil. Method: Fourteen healthy (nine women and five men), aged between 18 and 25 years were randomly selected. Both ankles were assessed by two trained examiners with the water plethysmographer, while a third examiner recorded the measures. Three measures of each ankle were obtained by the two investigators in an alternate way to investigate their intra- and inter-rater reliability. Twenty-six measures were also obtained with the water plethysmographer and were compared with the gold standard measures obtained with the water displacement. Intra-class correlation coefficients (ICCs) were employed to evaluate the intra- and inter-rater reliability, whereas paired Student t-tests and Pearsons correlation coefficients were calculated to establish the validity of the water plethysmographer measures. Results: The results demonstrated excellent intra- and inter-rater reliability levels (CCI=0.99). No differences were found between the measures obtained with the water plethysmographer compared to those of the test tubes (p=0.40). Pearsons correlation coefficient showed high magnitude and significance level between the measures (r=1,0; p<0.0001). Conclusions: The findings demonstrated that the water plethysmographer showed to be a reliable and valid instrument for measuring the ankle/foot volume.