Interobserver Variability in Esophageal Body Measurements With High-resolution Manometry Among New Physician Users

Abstract

To evaluate interobserver variability among 4 new physician users on measures of esophageal body function. Esophageal high-resolution manometry allows observation of esophageal motility by pressure topography plots. Little is known about the interobserver variability among physicians. Two resident and 2 fellow level physicians each interpreted 10 liquid swallows of 20 esophageal high-resolution manometry studies (n = 200 swallows) using the BioVIEW Analysis Suite (Sandhill Scientific Inc.). Studies evaluated were from patients referred for evaluation of dysphagia but found to have normal esophageal manometry and complete liquid bolus transit. Physicians received an orientation session and reviewed recent literature. Each physician recorded contractile front velocity (CFV) and distal contractile integral (DCI) for each liquid swallow. Interobserver agreements for CFV and DCI were assessed by intraclass correlation (ICC) values. Linear correlations between measurements by 2 readers were assessed using linear regression modeling techniques. CFV and DCI values of up to 200 data points were analyzed. Four reader results for CFV and DCI showed strong agreement although stronger for DCI measures (ICC = 0.94; range, 0.91 to 0.98) in comparison with CFV (ICC = 0.79; range, 0.52 to 0.82). Further correlation was performed with 2 readers; readers 1 and 2 revealed excellent correlation for DCI (r = 0.95, P < 0.001) and good correlation for CFV (r = 0.61, P < 0.001). With a thorough orientation session, good to excellent agreement for CFV and DCI measurements can be obtained from new physician users. CFV measures exhibit greater interobserver variability possibly due to the artifact produced by intraesophageal pressurization.