Abstract
Introduction: Respiratory muscle strength can be evaluated by static measurements of maximal inspiratory pressure (MIP), and maximal expiratory pressures (MEP) through a mouthpiece. Due to many types of digital and analog manovacuometers it is necessary to assess the equivalence of values. Objective: To assess the agreement between devices and to compare them against the predicted values for the healthy population. Method: A prospective and cross-sectional study assessed 120 patients with lung disease using digital (MVD 300 GlobalMed®) and analog (Commercial Medical®) manovacuometers. Patients were evaluated with both devices. Measures were analyzed in each test and the results were compared with predicted values in the literature. Results: The mean MIP of digital and analog manovacuometers were -72.6 (SD±26.5) and -71.0(SD±25.2); MEP 93.6(± 34.5) and 87.4 (±26.6).There was an agreement in MIP and MEP between the devices evaluated. According to the intraclass correlation coefficient (ICC), MIP (ICC=0.876) obtained a higher value than MEP (ICC=0.781). There was no significant difference in values for MIP (p= 0.297) obtained with both devices but there was a significant difference for MEP (p=0.000). The analog MEP was lower than digital MEP in 72 patients. We found a good agreement between the devices when classifying the values below or above the predicted range, (Kappa = 0.677 to 0.535 for MIP and MEP). Conclusion: There is an agreement between digital and analog manovacuometers. There was no statistical difference in MIP evaluation. There was an agreement in measures when classified by predicted values.
- © 2014 ERS