Deegan and colleagues (2018) stated that there remains no gold standard for quantification of voluntary pelvic floor muscle (PFM) strength, despite international guidelines that recommend PFM assessment in females with UI. In this study, methods currently reported for quantification of skeletal muscle strength across disciplines were systematically reviewed and their relevance for clinical and academic use related to the pelvic floor were described. These investigators performed a systematic review via Medline, PubMed, CINHAL, and the Cochrane database using key terms for pelvic floor anatomy and function were cross-referenced with skeletal muscle strength quantification from 1946 to 2016. Full text peer-reviewed articles in English having female subjects with UI were identified. Each study was analyzed for use of controls, type of methodology as direct or indirect measures, benefits, and limitations of the technique. A total of 1,586 articles were identified of which 50 met the inclusion criteria; 9 methodologies of determining PFM strength were described including: digital palpation, perineometer, dynamometry, electromyography (EMG), vaginal cones, ultrasonography, magnetic resonance imaging (MRI), urine stream interruption test, and the Colpexin pull test; 32 % lacked a control group. The authors concluded that technical refinements in both direct and indirect instrumentation for PFM strength measurement are allowing for sensitivity. However, the most common methods of quantification remain digital palpation and perineometry; techniques that pose limitations and yield subjective or indirect measures of muscular strength. Moreover , they stated that dynamometry has potential as an accurate and sensitive tool, but is limited by inability to assess PFM strength during dynamic movements.