3.a Arabic Female Sexual Function Index (FSFI)
The Arabic FSFI is a 19-item self-report tool that is both simple and comprehensive. It was utilized in both groups to assess the six major components of women's sexual function: desire, arousal, lubrication, orgasm, patient satisfaction, and pain. This tool included a variety of response options: the first two questions offered five alternative answers, while the remaining questions were graded on a scale of zero to five. The responses were then combined and multiplied by particular factors (0.6 for questions 1 and 2, 0.3 for questions 3–10, and 0.4 for questions 11–19) to determine the scores. The grading method ranged from 2 to 36, with a score greater than 26.5 indicating a satisfying sexual life and a score less than 26.5 indicating an impairment in sexual function [15].
The Arabic FSFI's validity, reliability, and local acceptance as a tool for assessing for female sexual dysfunction in Egypt's population have been established. The test-retest reliability ranged from 0.92 to 0.98 for both the overall score and the individual domain scores. Internal consistency among domains was equally high, with values ranging from 0.85 to 0.94. Furthermore, the Arabic FSFI demonstrated high discriminant validity. Overall, the Arabic FSFI performed admirably, with an area under the curve (AUC) of 0.985 and a 95% confidence interval (CI) of 0.978 to 0.992 [15].
3.b Ultrasound Imaging
All ultrasound measurements were performed by a trained physical therapist, who had 5 years of experience in diagnostic and rehabilitative ultrasonography imaging and a certified postgraduate diploma in ultrasound techniques. An ultrasound imaging device (Mindary DP10, Curvilinear probe, with 2–5 MHz frequency, Serial number; bn- 75013216, China) was used for evaluation of pelvic floor muscle force, for all participants in both groups.
Assessment of Pelvic Floor Muscle Force
An ultrasound imaging device with a 5 MHz curvilinear transducer was used to assess the PFM force in both groups. The measurements were carried out using a standardized bladder-filling protocol, which included instructing the participant to empty the bladder one hour before the test, followed by drinking 450 to 500 ml of water and not voiding until after the assessment, ensuring an optimal acoustic window. The subject was in a crock-lying posture, with the lumbar region neutral and the hips and legs flexed at a 60° angle. The ultrasonic transducer was placed horizontally above the symphysis pubis, squarely at the midline of the abdomen, at an angle of about 60° from vertical [17].
Participants were instructed to perform three maximum contractions of their PFMs in order to assess the posterior bladder wall displacement caused by PFM contractions. A defined border reflecting the location of the most significant observed displacement was consistently visible and chosen for measurement throughout the movement. The image has been taken at the maximal displacement point. The woman relaxed her PFMs after the image was recorded. The investigator then calculated the displacement by measuring the distance from the initial point in the static image. The investigator was not informed of the measurement value until the caliper was properly positioned at the final point. The transducer was kept stationary throughout the operation to preserve a constant vision field between rest and maximum contraction. The transducer was kept stationary throughout the procedure. For statistical analysis, the average of the three measurements was utilized [17]. The inter-rater reliability of this device for measuring PFM force was found to be good, with intra-rate correlation coefficient (ICC) values of 0.81 and 0.7123, respectively. Similarly, the intra-rater reliability was also good, with ICC values of 0.98 and 0.9841, respectively [18] Fig. 1.
3.c Pelvic tilt is measured using a spinal mouse. ( DIAG, Fehraltorf, Switzerland), a computer-assisted and noninvasive device. During measurements, the participants were in underwear and had no shoes. The spinal processes of the vertebrae C7-S3 were labeled. For measurement, the spinal mouse device was moved from top to bottom along the spine. The evaluation was carried out with the individuals standing erect and in the maximum trunk flexion and maximum trunk extension positions. Sagittal curvatures of the thoracic spine (T1-2 to T11–12) and lumbar spine (T12–L1 to the sacrum) and sacral position [19]
Sample size determination and statistical analysis:
Sample size calculation was performed using G*POWER statistical software (version 3.1.9.2; Franz Faul, Universitat Kiel, Germany) based on data on pelvic tilt derived from a pilot study conducted on 10 subjects in each group, which revealed that the required sample size for this study was 50 subjects in each group. The calculation is made with α = 0.05, power = 80%, and effect size = 0.57.
Statistical analysis:
Unpaired t test was conducted for comparison of subject characteristics between groups. Normal distribution of data was checked using the Shapiro-Wilk test. Levene’s test for homogeneity of variances was conducted to test the homogeneity between groups. Unpaired t test was conducted for comparison of, PFM, FSFI and pelvic tilt between groups and Mann-Whitney test was conducted for comparison of VLQ. The level of significance for all statistical tests was set at p < 0.05. All statistical measures were performed through the statistical package for social sciences (SPSS) version 25 for windows.