Viability and reliability among evaluators for vital capacity measured by ventilometer in healthy individuals

Abstract

INTRODUCTION: Vital capacity (VC) assessment is a relevant respiratory assessment method, since its data contribute to the diagnosis of diseases and alterations of this system. OBJECTIVES: The aim of this study was to evaluate the feasibility and the relative and absolute reliability of CV measured by the ventilometer. MATERIALS AND METHODS: A cross-sectional study was conducted between September and October 2010, where healthy individuals were included in a hospital in the city of Salvador / BA.. CV measurements were performed in the three moments through the ventilometer, being performed by two different raters (A and B). The first measure was reviewed by the observer A (A1), the second by observer B and the third again by observer A (A2). For inter-rater reliability, we used the measures A1 x B and B x A2 and intra-rater A1 x A2. RESULTS: The sample was composed of 30 subjects, mean age 29.4 ± 6.0 years. There was no difference in the comparison of means (A1 x B, p = 0.55, B x A2, p = 0.62 and A1 x A2, p = 0.40). The intra-rater reliability relative was 0.97 (p = 0.0001) and inter-rater 0.87 (p = 0.0001) and 0.97 (p = 0.0001). The absolute reliability showed agreement, but with variable bias (- 0.09, - 0.05 and - 0.03). CONCLUSION: There was a relative high reliability and moderate absolute reliability of vital capacity measured by the ventilometer.