Reliability in the measurement of maximum inspiratory pressure and inspiratory capacity of a physiotherapist in training

ABSTRACT The objective of this study was to explore the impact of clinical experience on the reliability and concordance of maximal inspiratory pressure (MIP) and inspiratory capacity (IC) measurements in a period of clinical training. For convenience, 37 participants in a body plethysmograph were evaluated by an experienced physiotherapist (EF) and a novice physiotherapist (NF). Intra-Class Correlation Coefficient (ICC) was used to analyze the reliability of the MIP and IC tests; to explore the individual differences, the Bland-Altman (gB/A) graphs were used. ICC analysis in three trials showed excellent inter-rater reliability (ICC 1st: 0.914; ICC 2nd: 0.915; ICC 3rd: 0.925) for the MIP test and (ICC 1st: 0.955; ICC 2nd: 0.965; ICC 3rd: 0.970) for the IC test. However, concordance according to gB/A among the evaluators showed a systematic trend with higher absolute scores for EF of 9.2 cmH2O in MIP, and of 0.06 L in IC, respectively. The results suggest that NF acquired reliable technical and discriminative skills for the MIP and IC test, but patients tended to improve performance with an experienced assessor. The evaluator’s experience influences the results obtained from the measurement of the MIP in the subjects; the formation of a NF requires incorporating more skills to recognize a sincere and maximum effort.