# Visualization of Caregiving Posture and Risk Evaluation of Discomfort and Injury
## 4 Discussion
involved in caregiving tasks and made adjustments to the additional scoring rules of the REBA method. Our C-REBA method offers caregivers a more accurate and targeted evaluation of the risk levels associated with caregiving postures. The original Extra A scoring rule is related to the load on the body, ignoring the injury to the body caused by the asymmetric load. Asymmetric loads tend to cause muscle injury on one side of the body, making a great impact. We found notable differences in caregiving power position and COG change trajectory between experienced and inexperienced caregivers, and then we reconstructed the scoring rules of Extra A from the perspective of the COG trajectory. The asymmetric load could be directly reflected in the position change of the COG between the feet. Keeping the COG position in the middle of the feet largely avoided the impact of the asymmetric load. It was also closely related to the caregiving power position. We converted asymmetric loads into the COG position trajectory between the feet to monitor the trend of asymmetric loads and incorporate it into the evaluation rule of C-Extra A. This ensured that C-REBA achieved comprehensive evaluation of caregiving tasks from the level of the asymmetric load. The original Extra C rule focused on maintaining fixed positions and repeating small ranges of action. There were differences in the load-bearing time and the range of caregiving movements between the Inexp and Exp groups. The load-bearing time was directly proportional to the risk of musculoskeletal discomfort and injury. The greater the change in the COG height, the more work the waist did, which was related to the maintenance of the power position [38, 39]. The effects of the load-bearing time and COG height changes were ignored by the original REBA method. We took the Exp group as the standard for load-bearing time and COG height variation, and we integrated this into the evaluation rules of the Extra C rules. The evaluation results of C-REBA indicated that the role of C-Extra C was to distinguish the Exp group from the Inexp group. Our research also found Stages 2, 3, 4 to be the most meaningful postural intervention phases for the inexperienced caregivers. Therefore, we integrated the load-bearing time and COG height change factors into the C-Extra C rules. Research findings have consistently demonstrated a heightened susceptibility to musculoskeletal injuries among inexperienced caregivers when compared to their experienced counterparts [40, 41]. This susceptibility is especially evident in physically demanding tasks, including transferring, lifting, and repositioning patients, and inexperienced caregivers are more prone to experiencing muscle strains and contusions [42]. Unfortunately, little information has been reported in the literature about the physical demands placed on inexperienced caregivers and any association with musculoskeletal injury [43]. Furthermore, the lack of research scrutinizing posture disparities between experienced and inexperienced caregivers, particularly regarding caregiving power positions, has resulted in a lack of clarity among inexperienced caregivers regarding appropriate caregiving power positions. While sporadic face-to-face training sessions on caregiving postures might exist, they are not wildly accessible. Consequently, the regular and timely correction of incorrect postures through repetitive practice presents significant challenges for inexperienced caregivers [44]. Importantly, the power position has demonstrated a certain correlation with the COG [29], and our study also demonstrated significant differences in COG trajectories between the experienced and inexperienced groups. Consequently, visualizing the COG trajectories provided valuable feedback on power positions, allowing inexperienced caregivers to make necessary adjustments based on the trajectory of the COG and the C-REBA scores. This facilitated the development of enhanced proficiency in executing power positions during caregiving.