Department of Physical Therapy Student Theses, Dissertations and Capstones

Document Type


Degree Name

Doctor of Philosophy (PhD) in Physical Therapy

Copyright Statement

All rights reserved. This publication is intended for use solely by faculty, students, and staff of Nova Southeastern University. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, now known or later developed, including but not limited to photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author or the publisher.


College of Health Care Sciences - Physical Therapy Department

First Advisor

Leah Nof

Second Advisor

Alicia Fernandez-Fernandez

Third Advisor

Karen Abraham

Publication Date / Copyright Date



Nova Southeastern University


Purpose: Diastasis recti abdominis (DRA) is a condition where the medial rectus bellies separate at the linea alba. A DRA can negatively impact posture, trunk and pelvic stability, pelvic floor muscular control, respiration, trunk movement, and abdominal viscera support. The purpose of this research is to determine whether tools used in the clinic effectively screen for DRA. Specifically, this study compared the reliability, validity, and diagnostic accuracy of finger width, tape measure, and calipermeasurements to the clinical best standard, ultrasound imaging. Additionally, the study investigates whether there is a correlation between DRA and low back pain and pelvic floor dysfunction. Participants: A sample of convenience of 49 men and women ranging from 18 to 64 years and female parity ranging from nulliparous to multiparous. Methods: This is a clinimetric, test-retest study. Two examiners measured the distance between the rectus bellies (interrecti distance or IRD) via finger widthpalpation, tape measure, and caliper under two conditions: at rest and during an abdominal crunch. Measurements were taken at two locations, above and at the umbilicus. A sonographer measured the IRD using ultrasound imaging under the same conditions and at the same locations. Participants returned within 7 days and the clinical measures were repeated. Examiners were blinded to measurements taken by the different examiners during the two measurement days. Results: Measurements taken with the tape measure had the strongest interrater reliability (moderate), followed by caliper (fair to moderate), then finger width palpation (poor to moderate). Tape measure also exhibited the strongest intrarater reliability ranging from good to very good (ICC = 0.77–0.83). Finger width palpation followed with good intrarater reliability (ICC = 0.63–0.76) and the caliper ranged from moderate to good (ICC = 0.53–0.61). Concurrent validity was fair to moderate for finger width palpation(ICC = 0.36–0.56) while the other measurement tools were deemed fair (ICC = 0.21–0.39). All three measurement tools had excellent specificity (96.3–100%) but low sensitivity (< 25%). Urinary incontinence and DRA were correlated with a moderate effect size and 4.9 odds ratio. Conclusions: Methods commonly used to screen for DRA have moderate interrater reliability, good to very good intrarater reliability, fair to moderate concurrent validity, and excellent specificity with low sensitivity. DRAand urinary incontinence are correlated.


Physical Therapy


Diastasis recti, Interrecti distance, Linea alba, Reliability, Validity