## 4 Discussion
The flexometer proved equally reliable as the goniometer for intrasession and intersession measurements and offers the additional advantage of allowing a single therapist to conduct the test without assistance. However, its bulkiness and higher cost limit its practicality in clinical settings. The goniometer, while reliable, lacks the convenience of single-operator use provided by the flexometer. The tape measure showed lower intersession reliability when directly recording distances but improved when used with trigonometric methods. Nonetheless, this method may require calculations that are less practical in busy clinical environments. Later, [PERSON] et al. [35], conducted one study assessing the psychometric properties of a hand-held inclinometer commonly utilized during SLR testing. Unlike [PERSON] et al., who employed three different instruments, [PERSON] et al. focused solely on the hand-held inclinometer and its validity compared to a digital inclinometer and a digital goniometer. Methodologically, [PERSON] et al. measured the limb elevation angle rather than just hip flexion, integrating the contribution of pelvic and lumbar spine motion. The hand-held inclinometer produced excellent intra-rater reliability (ICCs: 0.95 to 0.98), with an SEM ranging from 0.54\({}^{\circ}\) to 1.22\({}^{\circ}\) and a MDC\({}_{95}\) between 1.50\({}^{\circ}\) and 3.41\({}^{\circ}\). These findings indicate that the hand-held inclinometer is a reliable and valid tool for assessing limb elevation during SLR tests, with higher precision and practicality compared to the tape measure or goniometer methods described by [PERSON] et al. Moreover, [PERSON] et al. emphasized the inclinometer's ability to capture comprehensive motion, including contributions from the pelvis and lumbar spine, making it a better fit for assessing mechanosensitivity during neurodynamic testing. This broader construct measurement aligns with the clinical needs for evaluating neural involvement during SLR tests. Comparing these estimates with the values obtained in this study, we found slightly better reliability and accuracy of measurements using Kinovea. One potential explanation for this finding lies in the methodological advantage provided by video-based analysis with Kinovea. Unlike [PERSON] et al., our approach enabled the precise control and monitoring of compensatory mechanisms in the lower limb, such as unintended knee flexion or rotational deviations. These compensations, if not addressed, can introduce variability and reduce the accuracy of range of motion measurements. By minimizing these compensatory movements through careful visual analysis, we ensured that the angles recorded more accurately reflected the true hip flexion or limb elevation, enhancing the reliability of our measurements. Although both studies incorporated the patient's positive response to the maneuver as a determinant of the endpoint, the additional control of compensatory lower limb movements in our methodology provided a distinct advantage. This added layer of precision likely contributed to the improved reliability and accuracy observed in our results, underscoring the benefits of integrating video analysis into clinical and research settings. Statistical methods also differed between the studies [34; 35]. While [PERSON] et al. [34] utilized [PERSON]'s alpha coefficients and ANOVA for reliability assessment, [PERSON] et al. [35] relied on ICCs, SEM, and Bland-Altman analysis to evaluate the agreement between instruments. Furthermore, [PERSON] et al. examined construct validity, revealing strong correlations between the hand-held inclinometer and the digital inclinometer (r = 0.98-0.99) but also identifying discrepancies with the digital goniometer (\(\sim\)10\({}^{\circ}\) differences due to the goniometer measuring hip flexion alone). Reporting the ICCs, SEM, and MDC offers significant advantages over [PERSON]'s alpha in reliability studies.