Validating a clinical measure of levator hiatus size.

Abstract

We evaluate the interrater reliability of levator hiatus (LH) size and correlate size to other measures of muscle function. Participants were examined independently by 2 examiners. During maximal contraction of the levator ani, the muscle was assessed by using Brink's scale. The LH was measured in the transverse and sagittal dimensions by digital palpation. The paired t test was used to compare continuous variables and Spearman's coefficient was used for correlations. The mean LH transverse was 4.5 cm and the mean LH sagittal was 3 cm. The inter-rater correlation for the LH transverse measurement was 0.6 (P < .01) and 0.8 (P < .01) for the LH sagittal measurement. The correlations between the LH size and Brink's scale were moderate (correlation coefficient -0.4 to -0.5, P < .01). Eighty-three percent of measurements were within 1 cm. This technique for clinical measurement of levator hiatus size shows good interrater reliability.