Intertester and Intratester Reliability of Chest Excursion Measurements in Subjects Without Impairment

Abstract

Purpose: Chest excursion measurements are commonly used to assess the effect of disease on chest wall motion. The purpose of this study was to evaluate intertester and intratester reliability of chest excursion measurements. Methods: We collected data on 20 healthy subjects between the ages of 20 and 69 who were recruited via a quota sampling procedure. We measured chest excursion during 2 slow vital capacity maneuvers at 2 separate sites (axillary and xiphoid) in a standing position. Measurements were taken by 3 different investigators to determine intertester reliability. Measurements were taken by each of the investigators during 2 separate trials to determine intratester reliability. Data collection for each subject took place in one testing session. We calculated intraclass correlation coefficients (ICC) using model (2,k) for intertester reliability and model (3,k) for intratester reliability. Results: ICCs for intertester reliability were 0.94 for the axillary site and 0.95 for xiphoid site. Intratester reliability ICCs were 0.92 for the axillary site and 0.96 for the xiphoid site. Conclusions: This study demonstrated excellent intertester and intratester reliability of chest excursion measurements in subjects without impairment across a wide age range. Results also suggest that reproducibility of chest excursion measurements is better when measured at the xiphoid than the axillary site.