Bump et al (1991) Assessment of kegel pelvic muscle exercise performance after brief verbal instruction. Am J Ob Gyn 165.

The authors conclude that simple verbal or written instruction may not adequately prepare a woman for a home program that involves pelvic muscle contractions, also termed Kegels. Clinically, this conclusion leads to the importance of objective measures to ascertain accuracy of the instructed task. Perineal observation, abdominal wall observation, external palpation of perineum and abdominal wall, perineometry, pressure biofeedback, and digital palpation are methods that can be used clinically to determine that a patient is correctly completing a pelvic muscle contraction.

Frawley H et al (2006) Effect of test position on pelvic floor muscle assessment. Int Urogyn J. Vol 17, Issue 4, pp365-371.

Supra-pubic trans abdominal ultrasound is more sensitive in assessment of the pelvic floors lifting action.

Messelink B (2005) Standardisation of Terminology of Pelvic Floor Muscle Function and Dysfunction: Report From the Pelvic Floor Clinical Assessment Group of the International Continence Society. Neurourology and Urodynamics. 24:374-380.

The current recommendation by the International Continence Society (Messelink et al 2005) is to adopt a new, simpler grading scale of 4 points: absent, weak, normal (interpreted as ‘moderate’) and strong to reflect the total of the tightening, lifting and squeezing action.

Stafford, R. Ashton-Miller J, Constantinou C, Hodges P. 2013 A new method to quantify male pelvic floor displacement from 2D transperineal ultrasound images. Urology, 81(3):685-689.

This new method of trans-perineal US allows concurrent investigation of displacements of points previously validated for females in addition to new measures (SUS and BC) with potential to influence male pelvic floor function.