Application of perineometer in the assessment of pelvic floor muscle strength and endurance: a reliability study.

Despite different studies on the reliability of pelvic floor muscle assessment, there is still no general consensus on the most valid and reliable method. The purpose of this study was to investigate the intra-rater (within-day and between-days) reliability of perineometer in the assessment of pelvic floor muscle strength and endurance. Following ethical approval, 15 healthy women aged from 22 to 50-years old, with no history of low back pain were recruited. The Peritron perineometer instrument was used to measure pelvic floor muscle strength and endurance. Two measurements were taken on the same day with an hour interval to assess within-day reliability and the third measurement was taken five days later to determine between-days reliability. Intraclass Correlation Coefficients (ICCs) and the level of agreement between measurements were used for data analysis. The high ICC values (0.95 for strength and 0.94 for endurance) and high level of agreement between measurements indicated high within-day reliability for pelvic floor muscle strength and endurance. The perineometer was also shown to be reliable for between-days measurements with high ICC (0.88 for strength and 0.83 for endurance) and high level of agreement between measurements. The results demonstrated that the perineometer appears to be a highly reliable method of measuring pelvic floor muscle strength and endurance when measurements are taken in healthy subject by the same investigator.