Fig. 1.
Frequency dependences of respiratory impedance, respiratory resistance (Rrs) and reactance (Xrs) at 4–36 Hz, during a whole breath, inspiratory phase and expiratory phase, were examined. The Rrs (a) and Xrs (b) of all rheumatoid arthritis (RA) cases (n = 69) are shown. Values during inspiratory and expiratory phases are mean ± SD (cmH2O/L/s). Averages of Rrs and Xrs during a whole breath are also shown (dashed lines). *Significant difference (P < 0.05) between inspiratory and expiratory phases by two-way repeated measure ANOVA, followed by Bonferroni test for post hoc analysis