Abstract
OBJECTIVES: High-resolution anorectal manometry (HR-ARM) is a diagnostic test assessing anorectal neuromuscular function in children with constipation and/or fecal incontinence. Interrater reliability of HR-ARM in children has not been previously studied. The aim of this study was to assess the interrater reliability of pediatric HR-ARM studies. METHODS: Ten pediatric gastroenterologists specialized in neurogastroenterology and motility analyzed ten deidentified pediatric HR-ARM studies using dedicated analysis software (Solar GI HRM v9.1, MMS, Enschede, the Netherlands). Anal canal resting pressure, squeeze pressure and duration, presence of the rectoanal inhibitory reflex (RAIR), bear down maneuver (normal/abnormal), and final interpretation of the study (normal/abnormal) were evaluated. Fleiss' Kappa (κ) and intraclass correlation coefficient (ICC) were used for categorical and continuous data, respectively. RESULTS: Interrater reliability was excellent for resting pressure (ICC 0.97, 95% confidence interval [CI 0.93-0.99), squeeze pressure (ICC 0.97, 95% CI 0.94-0.99), and squeeze duration (ICC 0.93, 95% CI 0.85-0.98). A fair interrater agreement for the RAIR (κ = 0.35) was seen, and a moderate interrater agreement was seen for interpretation of the bear down maneuver and the final interpretation of the study either being normal or abnormal (κ = 0.50 and κ = 0.43, respectively). CONCLUSIONS: This study demonstrated excellent interrater reliability in assessing HR-ARM anal canal resting pressure, squeeze pressure, and squeeze duration and suboptimal reliability in interpreting the detection of a RAIR and bear down maneuver. These findings highlight the need for standardization of HR-ARM protocols and interpretation criteria in children.