Pelvic floor ultrasound imaging: are physiotherapists interchangeable in the assessment of levator hiatal biometry?

Abstract

To evaluate inter-examiner reliability in the ultrasound (US) assessment of levator hiatal dimensions when different physiotherapists perform independent data acquisition and analysis. In this cross-sectional observational study, 14 asymptomatic nulliparous women were imaged at rest, during pelvic floor muscle contraction, and during Valsalva manoeuvre by two physiotherapists using three-dimensional (3D) and four-dimensional (4D) transperineal US. Examiners each measured the dimensions of the levator hiatus (area and antero-posterior and transverse diameters) from the US volumes they respectively acquired. Inter-examiner reliability was determined using intra-class correlation coefficients (ICCs), and inter-examiner agreement was determined using Bland-Altman analyses. The ICC results demonstrated very good inter-examiner reliability (ICC=0.84-0.98); Bland-Altman results showed high inter-examiner agreement across all measurements. Trained examiners may be considered interchangeable in the US assessment of levator hiatal biometry. Overall, trained physiotherapists using transperineal US imaging to assess levator hiatal biometry can be confident when comparing their own clinical findings to those of their colleagues and to findings published in the literature.