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. 2025 Jul 14;20(7):e0327781. doi: 10.1371/journal.pone.0327781

Predictors of quality of life in individuals with non-traumatic unilateral transtibial amputation

Tahereh Alavi 1, Maryam Jalali 1,*, Behshid Farahmand 1, Taher Babaee 1
Editor: Raffaele Vitiello2
PMCID: PMC12258552  PMID: 40658695

Abstract

Purpose

Quality of life is a crucial outcome in evaluating adjustment to prostheses for individuals with non-traumatic lower limb amputation (LLA). This study aimed to identify prostheses-related factors that predict the quality of life in people with non-traumatic, unilateral, transtibial amputation.

Materials and methods

This cross-sectional study surveyed 168 people who have experienced non-traumatic, unilateral, transtibial amputations and use prosthesis. They completed the 12-item short-form (SF-12) health survey and the comprehensive lower limb amputee socket survey (CLASS). We did correlation analyses to explore relationships between the variables and quality of life, followed by multiple regression analyses to assess their impact on quality of life outcomes.

Results

Quality of life had a strong positive association with comfort (r = 0.65, p = 0.001). There was a moderate positive association with socket stability (r = 0.46, p < 0.001) and suspension (r = 0.48, p = 0.001), as well as a weak positive association with appearance (r = 0.35, p = 0.001). In the final regression model, the comfort subscale of CLASS was the strongest predictor of quality of life (β = 0.51, p = 0.001).

Conclusion

This study highlights that prosthesis socket comfort is the primary prosthesis-related factor predicting the quality of life for individuals with non-traumatic, unilateral, transtibial amputation. Thus, rehabilitation should prioritize modifiable factors, especially optimal socket fitting. Identifying user needs is essential for better prosthesis use, as enhancements in other prosthetic components do not necessarily improve quality of life without considering socket comfort.

Introduction

Lower limb amputation (LLA) accounts for 80%−85% of all amputations and is primarily caused by vascular diseases [1]. The primary objectives of rehabilitation after LLA are to improve function and quality of life [2]. It is well-established that individuals who undergo non-traumatic LLA generally experience a lower quality of life compared to those with traumatic amputations or individuals without disabilities [35].

A 2017 systematic review assessed factors influencing the quality of life of people with LLA due to peripheral arterial occlusive diseases. It reported that factors such as older age and co-morbidities, notably diabetes, negatively influence the probability of successfully walking with a prosthesis and having a better quality of life. The studied population was mainly older than 65 years old, and approximately half had diabetes. The study found that the presence of arterial diseases in other organs adds to the comorbid burden of this population, combined with walking ability, which may be impaired before amputation [6]. These factors reduce their life expectancy and ability to walk with a prosthesis. This study suggested improving the quality of life of prosthetic users as a solution to extending rehabilitation. It found that the ability to move about effectively with a prosthesis is particularly crucial, as it significantly impacts the quality of life for non-traumatic amputees [6]. Torbjörnsson et al. investigated the impact of prosthetic use on the health-related quality of life of individuals who had LLA due to peripheral vascular disease. Even those who only used their prostheses for limited movement purposes (such as sitting in a wheelchair) experienced an improvement in their health-related quality of life after one year [7].

Quality of life has become essential in rehabilitation programs and an indicator to assess adaptability to the prosthesis [5]. Studies have indicated that the success rate for using lower limb prostheses ranges from 46% to 96% in amputees [812]. This success rate depends on several factors, including the prosthesis’ quality, the socket comfort, the strength of the residual limb muscles, proper selection of prosthetic components, residual limb length, and psychological, occupational, and economic needs [812].

In a clinical setting, amputees have emphasized that the most essential feature of a lower limb prosthesis is the comfort and quality of the socket fit [13,14]. Also, Baars et al. found that many transtibial prosthesis users were unsatisfied with their prosthesis, and several factors, including its appearance, properties (functional and physical properties), fit, functional use, and other related aspects, can influence people’s satisfaction with prostheses [15].

A well-fitted prosthetic socket that looks appropriate is typically better accepted by the patient. Additionally, a proper fit reduces pistoning movements and shearing forces on the residual limb, improving overall comfort and functionality [11,12,16]. Also, a suitable suspension system can help reduce residual limb rotation and vertical and horizontal movement within the prosthetic socket. This increased stability is strongly associated with amputees’ satisfaction and quality of life [1719]. On average, lower limb prosthesis users require nine visits annually for prosthesis-related issues, with 70% resulting from socket, suspension system, and residual limb problems [2022].

Research indicates that amputees with residual limbs that are either shorter or longer than the average length face distinct challenges related to the fitting of prosthetic socket [23,24]. In this regard, users dissatisfied with their prosthetic fitting may reject it or need to visit clinics frequently; a severe issue for prosthesis users can negatively affect their quality of life [25]. Moreover, different prosthesis foot types used by amputees can significantly impact their gait efficiency and various essential aspects of their daily lives. This includes overall mobility, balance, comfort, and satisfaction with their prosthesis [26,27].

Assessing the influencing factors on the quality of life of individuals with non-traumatic LLA is clinically important; however, there is limited information on these parameters. This study focused on identifying the impact of prosthetic fitting and components in predicting the quality of life of people with non-traumatic unilateral transtibial amputation.

Materials and methods

Study design and participants

This cross-sectional observational study was conducted between June and December 2022. We used a convenience sampling method to enroll the participants. The study protocol was approved by the ethics committee of Iran University of Medical Sciences (IR.IUMS.REC.1401.137).

The inclusion criteria included: 1) participants must be at least 18 years of age, 2) they should have had a non-traumatic unilateral below-knee amputation at least one year before the study, 3) they must have been using their current prosthesis for a minimum of three months, and 4) they should be able to read and write in Farsi (Persian).

Prior to participating in the study, all individuals provided written informed consent. Participants were required to complete two standardized assessments: the 12-item short-form (SF-12) health survey and the comprehensive lower limb amputee socket survey (CLASS). Researchers additionally collected demographic and clinical information from each participant. Throughout the process, participants had the opportunity to seek clarification from research staff regarding any aspects of the study. To ensure confidentially, participants completed all questionnaires anonymously without disclosing their personal identities.

The CLASS

The CLASS is a self-report instrument designed to assess the satisfaction of people with LLA with their prosthetic socket. The survey comprise 15 questions organized into four subscales: stability, suspension, comfort, and appearance. The first three subscales contain four items each, while the appearance subscale consists of three items. The stability, suspension, and comfort subscales evaluate satisfaction while sitting, standing, walking, and climbing stairs with their prosthesis. The appearance subscale assesses satisfaction with the prosthesis’ appearance in three conditions: standing, sitting, and wearing tight pants. Each subscale has a score range of 1 to 4, and if none of the answers are applicable, the respondents can select the “not applicable” choice, which will be scored as zero. The total score for each subscale ranges from 0 to 100%, with 100% representing the highest level of satisfaction [9]. We used the Persian version of the CLASS questionnaire in this study [28].

The SF-12

This survey evaluates people’s quality of life and health in daily routines. It includes eight subscales that measure limitations in physical activity due to health problems, limitations in social activities due to physical or emotional issues, physical pain, mental health, and limitations in everyday activities due to emotional problems, vitality, and general health perception. SF-12 items are grouped into two main components: physical and mental. The answers are based on the Likert scale, ranging from 1 to 6 [29]. All answers are summed up to calculate the overall score. We used the valid and reliable Persian version of SF-12 in our study [30].

Statistical analysis

We used the statistical package for social sciences (SPSS) software version 20.0 for the statistical analyses. To assess data normality, we conducted a one-sample Kolmogorov-Smirnov test. To evaluate the correlation between the target variables and quality of life, we employed Spearman’s rank correlation coefficient analysis. R values of 0–0.19 were considered very weak, 0.2–0.39 weak, 0.40–0.59 moderate, 0.6–0.79 strong, and 0.8–1 as very strong correlations [31]. Multiple regression analysis was run to investigate the impact of the predicting variables (including stability, comfort, suspension, appearance, prosthetic foot type, socket insert type, and residual limb length) on quality of life. The least required sample size for conducting multivariate regression analysis was calculated with this formula: N> (50 + 8*m) [32], where m represents the number of independent variables. with 13 independent variables in this study, the calculation yielded a requirement of at least 154 cases to ensure robust statistical power for the analysis.

Results

In total, 195 people with non-traumatic, unilateral, transtibial amputation were invited to participate in this study. After the initial data evaluation, we found that two participants had not completed the questionnaires and were excluded. Additionally, 25 participants who had a traumatic amputation were also excluded. Finally, the data of 168 people with non-traumatic, unilateral, transtibial amputation (81% men) was evaluated.

The participants had a mean age of 52.3 ± 14.4 years and an average body mass index of 26.97 ± 4.80 kg/m2. Regarding socket inserts, the majority (53.6%) used a gel liner with a locking mechanism, while (41.7%) used foam liners and (4.8%) used gel liners without locking mechanisms. Prosthetic foot types were nearly evenly distributed: 52.4% (n = 88) had non-articulated feet, and 47.6% (n = 80) had articulated feet. Key temporal metrics (mean ± SD) included time since amputation (148.2 ± 166.6 months), prosthesis use duration (131.6 ± 153.7 months), and current prosthesis wear duration (43.4 ± 54.5 months) (Table 1).

Table 1. Demographic and clinical characteristics of the studied population (n = 168).

Variables Categorization No. (%)
Residual limb length Short (Shorter than 7.5 cm) 40 (23.8)
Moderate (Between 7.5 to 20.5 cm) 94 (56.0)
Long (20.5 cm and more) 34 (20.2)
Socket insert type Gel liner 98 (58.4)
Foam liner 70 (41.7)
Foot type Non-articulated 88 (52.4)
Articulated 80 (47.6)

Predictors of quality of life

A statistically significant positive correlation was observed between the overall SF-12 score and all subscale measures of the CLASS (Table 2). A multiple regression analysis was conducted using four independent variables (Table 3). Only one variable had a significant contribution to the model. Among the variables in the final model, the comfort subscale of CLASS had the highest beta value (beta = 0.51, p < 0.001) and was the only significant variable.

Table 2. Relationship between quality of life and the associated variables.

Independent Variable (Mean ± SD) Dependent variables Mean ± SD Correlation coefficient P-value
Total SF-12
(31.9 ± 8.7)
Stability 75.9 ± 21.1 0.46 ≤0.001
Suspension 75.8 ± 21.0 0.48 ≤0.001
Comfort 71.1 ± 21.7 0.65 ≤0.001
Appearance 52.9 ± 19.4 0.35 ≤0.001
Prosthetic foot type 1.4 ± 0.5 0.05 0.52
Socket insert type 1.5 ± 0.5 0.005 0.94
Residual limb length 1.9 ± 0.6 0.03 0.70

Abbreviations: SF-12, Short form 12; SD, standard deviation.

Correlation analyses: Spearman’s rho correlation. Significance level: < 0.05 underlined

Table 3. Multiple regression analysis result.

Variables Standardized Coefficient (beta) Tolerance Part VIF P-value
Stability 0.03 0.27 0.01 3.71 0.81
Suspension 0.12 0.28 0.06 3.53 0.27
Comfort 0.51 0.52 0.37 1.90 ≤0.001
Appearance 0.13 0.80 0.11 1.25 0.05

Total R2 = 0.44 for the multiple linear analysis.

Abbreviations: SF-12, Short form 12. Significance level: <0.05 underlined.

Discussion

People with LLA experience significant limitations in their overall performance, which can significantly affect their quality of life [33]. According to various studies, focusing on specific aspects of residual limb, prosthesis-related factors, and socket-related issues, especially socket comfort and fit, are crucial in improving amputees’ quality of life [14,22,34]. This is especially important for non-traumatic amputees who have a lower quality of life due to age, comorbidities, and inherent mobility restrictions. It is believed that by focusing on modifiable factors that affect quality of life and improving them, we can improve the quality of life in this population. Our regression analysis results revealed that the comfort subscale of CLASS is the strongest predictor of quality of life in people with non-traumatic, unilateral, transtibial amputation. Also, quality of life had a strong positive association with comfort, a moderate positive relationship with socket stability and suspension and a weak positive relationship with appearance (all via CLASS).

Based on our findings, only socket comfort contributed to a higher quality of life among the studied prosthetic-related parameters. According to previous studies, the core criterion for a well-fitting socket is the patient’s comfort [35]. Furthermore, proper socket fit and comfort are highly associated with higher prosthetic satisfaction and quality of life [16,28]. The prosthetic users feel comfortable when weight bearing is spread evenly over the entire residual limb [34].

Enhancing socket design requires establishing a strong connection between the socket and the residual limb [36]. Many prosthetists who participated in a qualitative, descriptive study identified that socket comfort leads to greater user satisfaction and use [37]. Our previous study showed that socket comfort was positively correlated with mobility (r = 0.52), suggesting that a more comfortable prosthetic socket may enhance mobility, which in turn can contribute to a better quality of life [38]. Comfortable prosthetic devices allowed users to be active longer, impacting their ability to carry out specific tasks. This ultimately influenced their participation in activities such as working jobs, caring for their families, or attending school [37]. Therefore, it can be concluded that prosthetic socket comfort may increase the prosthetic user’s willingness to take part in social interactions, potentially contributing to improved quality of life [39]. This finding was also reported by Matsen et al. [16] and Rouhani et al. [28].

In our study, there was a significant moderate positive correlation between socket stability and suspension and quality of life. Also, a weak positive relationship existed between appearance and quality of life. An appropriate suspension can reduce the residual limb’s rotary, vertical, and horizontal movement in the prosthetic socket, increasing the socket’s stability [40]. A precisely fitted prosthetic socket significantly reduces detrimental pistoning motion and shear stress at the residual limb interface. Previous studies also suggest that suitable fitting of the socket considerably affects the comfort, performance, satisfaction, and quality of life of people with LLA [18].

Prosthesis satisfaction is the amputees’ subjective and emotional evaluation of the prosthesis that is influenced by the appearance, properties, fit, and use [41]. Harness and Pinzur found a positive association between overall satisfaction and the prosthesis appearance [42]. Also, Matsen et al. found strong and significant positive correlations between prosthesis appearance and quality of life measured using a visual analog scale [16]. Our findings support Matsen et al.’s finding regarding the relationship between satisfaction with socket appearance and quality of life. However, this relationship was weak. This discrepancy may be attributed to differences in the study populations. Our participants were predominantly older adults with non-traumatic unilateral transtibial amputations, for whom the functional aspects of the prosthesis may outweigh aesthetic considerations. For these individuals, comfort, stability, and ease of use might play a more central role in influencing satisfaction and quality of life than appearance alone.

The considerable benefit of a prosthesis, in contrast to crutches and wheelchairs, is that it can almost entirely disguise the loss of a limb and, therefore, essentially eliminate the stigma associated with having a visible disability by restoring the appearance of the lost limb and its function [37]. This can explain why prosthesis appearance correlates with quality of life. Further investigations are required to understand this relationship better.

Our results show that quality of life had no significant relationship with prosthetic socket insert type. Hawari et al. demonstrated that amputees broadly use silicon liners. This is due to the advantages the silicone offers, such as protection of the residual limb skin, better suspension, and cosmetic appearance. However, itching and excessive perspiration were reported as adverse effects [34]. On the other hand, a systematic review showed that polyethylene foam insert users were more satisfied than silicon liners or polyurethane liners while sitting or walking on uneven terrain [41]. Nevertheless, Van de Weg and van der Windt conducted a comparative analysis of patient satisfaction levels across distinct prosthetic liner groups, including polyethylene foam, silicone liners, and polyurethane liners. They found no significant differences between these patients’ satisfaction [43].

Interpreting the relationship between socket insert type and quality of life by considering these studies shows that many factors influence interface type, and each liner type has advantages and disadvantages. Maybe that is why socket insert type does not directly affect the quality of life. This suggests that independent of socket type, if a socket insert provides comfort, it can significantly impact the quality of life of individuals with non-traumatic, unilateral, transtibial amputation.

Our results also show that quality of life is not significantly related to prosthetic foot type and residual limb length. We divided participants’ prosthetic foot types into articulated and non-articulated types. On the one hand, the results of a systematic review by Lathouwers et al. [44] is consistent with ours, showing that quasi-passive and active prostheses improve the quality of life compared to passive ankle-foot prostheses. On the other hand, the results of a study by Paradisi et al. [27] are inconsistent with ours. They compared the quality of life in hypomobile transtibial amputees by replacing a solid ankle cushion heel (SACH) foot with a multiaxial prosthetic foot. Their findings show that after replacing the SACH foot with a multiaxial foot, patients have maintained the same level of stability and perceived safety while presenting a slightly significant improvement in some critical clinical aspects of daily life, including overall mobility, balance, general comfort, and perceived satisfaction with prosthesis. Further in-depth studies are required to clarify the relationship between quality of life and prosthetic foot type. While previous studies emphasize the biomechanical and functional implications of residual limb length (including socket fit, energy expenditure, and prosthetic alignment) [23,37], we were unable to locate studies that explicitly confirm or refute its influence on quality of life. The current study categorized residual limb length into three groups: long, moderate, and short. Individuals with either short or long residual limbs were expected to experience a lower quality of life due to specific socket-fitting issues. These issues included bony stumps lacking sufficient soft tissue padding, smaller lever arms, and, as a result, lower power generation for long and short residual limbs, respectively.

An identified issue with amputation surgery is a lack of optimization of the residual limb for prosthetic fitting. This includes preserving as much length of the residuum as possible to improve socket fit [37]. Optimal residual limb length reduces the center of mass excursion, aberrant gait, and energy cost [45]. Besides, it has long been accepted that the resulting physiological demand is more significant if a lower limb amputation is more proximal [23]. On the other hand, a long residual limb is not optimal. Long-length residual limbs may lead to problems such as insufficient stump soft tissue coverage and insufficient space for adjusting prosthesis components [24]. Generally, the length of a transtibial residual limb should be 10 cm for every meter of the person’s height, or one inch for every foot of height, measured from the medial aspect of the tibial plateau to the cut end of the tibia [24]. However, the study did not find a correlation between residual limb length and quality of life. We inferred that the heterogeneous frequency distribution in groups, including 94 individuals with moderate residual limbs and 40 and 34 individuals with short and long residual limbs, may explain that result.

Limitations

Our study only evaluated socket comfort, stability, and suspension while doing activities such as sitting, standing, walking, and ascending/descending stairs (via CLASS). It does not include other vital situations like the time of day or proximity to dialysis, which is relevant for diabetic amputees. Future research should consider monitoring comfort, stability, and suspension throughout the day and their impact on the quality of life, especially for people with non-traumatic LLA with diabetes who use transtibial prostheses. Additionally, we have classified participants’ prosthetic foot designs into two primary categories: articulated (e.g., single-axis foot) and non-articulated (e.g., SACH). Notably, non-articulated designs, such as energy storage and return feet, utilize advanced material properties to dynamically simulate the three rockers of gait. These designs optimize biomechanical function during both the swing and stance phases, enhancing stability and propulsion. However, gaps remain in understanding how these structural differences affect long-term quality of life outcomes for individuals with unilateral transtibial amputations. Future studies should assess quality of life parameters across different foot types.

Conclusion

Determining factors required for lower limb prosthetic rehabilitation in people with LLA is essential for focusing on prosthetic and socket design and fitting because they provide the context of need and user issues. An interesting finding of our study is that prosthesis socket comfort is the only prosthesis-related factor that predicts quality of life in people with non-traumatic, unilateral, transtibial amputation. Some studies investigate factors, such as age and the presence of co-morbidities, which also affect the quality of life, but the problem is that they are not modifiable. Therefore, rehabilitation studies must focus on modifiable factors, particularly regarding prosthesis socket fitting. Correct identification of user needs for device use is necessary to adapt the device optimally; for example, we found that improving the prosthesis components does not necessarily lead to an increased quality of life, and socket comfort is crucial in this situation.

Supporting information

S1. The values behind the means, standard deviations.

(XLSX)

pone.0327781.s001.xlsx (17.6KB, xlsx)

Acknowledgments

The authors would like to express their gratitude to all participants involved in this study.

Data Availability

All relevant data are within the paper and its Supporting Information files.

Funding Statement

The author(s) received no specific funding for this work.

References

  • 1.Calabrese L, Maffoni M, Torlaschi V, Pierobon A. What Is Hidden behind Amputation? Quanti-Qualitative Systematic Review on Psychological Adjustment and Quality of Life in Lower Limb Amputees for Non-Traumatic Reasons. Healthcare (Basel). 2023;11(11):1661. doi: 10.3390/healthcare11111661 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 2.Pernot HF, Winnubst GM, Cluitmans JJ, De Witte LP. Amputees in Limburg: incidence, morbidity and mortality, prosthetic supply, care utilisation and functional level after one year. Prosthet Orthot Int. 2000;24(2):90–6. doi: 10.1080/03093640008726531 [DOI] [PubMed] [Google Scholar]
  • 3.Yilmaz M, Gulabi D, Kaya I, Bayram E, Cecen GS. The effect of amputation level and age on outcome: an analysis of 135 amputees. Eur J Orthop Surg Traumatol. 2016;26(1):107–12. doi: 10.1007/s00590-015-1709-z [DOI] [PubMed] [Google Scholar]
  • 4.England DL, Miller TA, Stevens PM, Campbell JH, Wurdeman SR. Mobility Analysis of AmpuTees (MAAT 7): Normative Mobility Values for Lower Limb Prosthesis Users of Varying Age, Etiology, and Amputation Level. Am J Phys Med Rehabil. 2022;101(9):850–8. doi: 10.1097/PHM.0000000000001925 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 5.Sinha R, van den Heuvel WJA, Arokiasamy P. Factors affecting quality of life in lower limb amputees. Prosthet Orthot Int. 2011;35(1):90–6. doi: 10.1177/0309364610397087 [DOI] [PubMed] [Google Scholar]
  • 6.Davie-Smith F, Coulter E, Kennon B, Wyke S, Paul L. Factors influencing quality of life following lower limb amputation for peripheral arterial occlusive disease: A systematic review of the literature. Prosthet Orthot Int. 2017;41(6):537–47. doi: 10.1177/0309364617690394 [DOI] [PubMed] [Google Scholar]
  • 7.Torbjörnsson E, Ottosson C, Boström L, Blomgren L, Malmstedt J, Fagerdahl A-M. Health-related quality of life and prosthesis use among patients amputated due to peripheral arterial disease - a one-year follow-up. Disabil Rehabil. 2022;44(10):2149–57. doi: 10.1080/09638288.2020.1824025 [DOI] [PubMed] [Google Scholar]
  • 8.Çalışkan Uçkun A, Yurdakul FG, Almaz ŞE, Yavuz K, Koçak Ulucaköy R, Sivas F, et al. Reported physical activity and quality of life in people with lower limb amputation using two types of prosthetic suspension systems. Prosthet Orthot Int. 2019;43(5):519–27. doi: 10.1177/0309364619869783 [DOI] [PubMed] [Google Scholar]
  • 9.Gailey R, Kristal A, Lucarevic J, Harris S, Applegate B, Gaunaurd I. The development and internal consistency of the comprehensive lower limb amputee socket survey in active lower limb amputees. Prosthet Orthot Int. 2019;43(1):80–7. doi: 10.1177/0309364618791620 [DOI] [PubMed] [Google Scholar]
  • 10.Gholizadeh H, Abu Osman NA, Eshraghi A, Ali S, Yahyavi ES. Satisfaction and problems experienced with transfemoral suspension systems: a comparison between common suction socket and seal-in liner. Arch Phys Med Rehabil. 2013;94(8):1584–9. doi: 10.1016/j.apmr.2012.12.007 [DOI] [PubMed] [Google Scholar]
  • 11.Hanspal RS, Fisher K, Nieveen R. Prosthetic socket fit comfort score. Disabil Rehabil. 2003;25(22):1278–80. doi: 10.1080/09638280310001603983 [DOI] [PubMed] [Google Scholar]
  • 12.Webster JB, Hakimi KN, Williams RM, Turner AP, Norvell DC, Czerniecki JM. Prosthetic fitting, use, and satisfaction following lower-limb amputation: a prospective study. J Rehabil Res Dev. 2012;49(10):1493–504. doi: 10.1682/jrrd.2012.01.0001 [DOI] [PubMed] [Google Scholar]
  • 13.Hagberg K, Brånemark R, Hägg O. Questionnaire for Persons with a Transfemoral Amputation (Q-TFA): initial validity and reliability of a new outcome measure. J Rehabil Res Dev. 2004;41(5):695–706. doi: 10.1682/jrrd.2003.11.0167 [DOI] [PubMed] [Google Scholar]
  • 14.Legro MW, Reiber G, del Aguila M, Ajax MJ, Boone DA, Larsen JA, et al. Issues of importance reported by persons with lower limb amputations and prostheses. J Rehabil Res Dev. 1999;36(3):155–63. [PubMed] [Google Scholar]
  • 15.Baars EC, Schrier E, Dijkstra PU, Geertzen JHB. Prosthesis satisfaction in lower limb amputees: A systematic review of associated factors and questionnaires. Medicine (Baltimore). 2018;97(39):e12296. doi: 10.1097/MD.0000000000012296 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 16.Matsen SL, Malchow D, Matsen FA 3rd. Correlations with patients’ perspectives of the result of lower-extremity amputation. J Bone Joint Surg Am. 2000;82(8):1089–95. doi: 10.2106/00004623-200008000-00004 [DOI] [PubMed] [Google Scholar]
  • 17.McCurdie I, Hanspal R, Nieveen R. ICEROSS--a consensus view: a questionnaire survey of the use of ICEROSS in the United Kingdom. Prosthet Orthot Int. 1997;21(2):124–8. doi: 10.3109/03093649709164540 [DOI] [PubMed] [Google Scholar]
  • 18.Baars ECT, Geertzen JHB. Literature review of the possible advantages of silicon liner socket use in trans-tibial prostheses. Prosthet Orthot Int. 2005;29(1):27–37. doi: 10.1080/17461550500069612 [DOI] [PubMed] [Google Scholar]
  • 19.Kristinsson O. The ICEROSS concept: a discussion of a philosophy. Prosthet Orthot Int. 1993;17(1):49–55. doi: 10.3109/03093649309164354 [DOI] [PubMed] [Google Scholar]
  • 20.Dickinson AS, Steer JW, Woods CJ, Worsley PR. Registering methodology for imaging and analysis of residual-limb shape after transtibial amputation. J Rehabil Res Dev. 2016;53(2):207–18. doi: 10.1682/JRRD.2014.10.0272 [DOI] [PubMed] [Google Scholar]
  • 21.Haggstrom EE, Hansson E, Hagberg K. Comparison of prosthetic costs and service between osseointegrated and conventional suspended transfemoral prostheses. Prosthet Orthot Int. 2013;37(2):152–60. doi: 10.1177/0309364612454160 [DOI] [PubMed] [Google Scholar]
  • 22.Pezzin LE, Dillingham TR, Mackenzie EJ, Ephraim P, Rossbach P. Use and satisfaction with prosthetic limb devices and related services. Arch Phys Med Rehabil. 2004;85(5):723–9. doi: 10.1016/j.apmr.2003.06.002 [DOI] [PubMed] [Google Scholar]
  • 23.Penn-Barwell JG. Outcomes in lower limb amputation following trauma: a systematic review and meta-analysis. Injury. 2011;42(12):1474–9. doi: 10.1016/j.injury.2011.07.005 [DOI] [PubMed] [Google Scholar]
  • 24.Isaacs-Itua A, Sedki I. Management of lower limb amputations. Br J Hosp Med (Lond). 2018;79(4):205–10. doi: 10.12968/hmed.2018.79.4.205 [DOI] [PubMed] [Google Scholar]
  • 25.Dillingham TR, Pezzin LE, MacKenzie EJ, Burgess AR. Use and satisfaction with prosthetic devices among persons with trauma-related amputations: a long-term outcome study. Am J Phys Med Rehabil. 2001;80(8):563–71. doi: 10.1097/00002060-200108000-00003 [DOI] [PubMed] [Google Scholar]
  • 26.Hsu M-J, Nielsen DH, Lin-Chan S-J, Shurr D. The effects of prosthetic foot design on physiologic measurements, self-selected walking velocity, and physical activity in people with transtibial amputation. Arch Phys Med Rehabil. 2006;87(1):123–9. doi: 10.1016/j.apmr.2005.07.310 [DOI] [PubMed] [Google Scholar]
  • 27.Paradisi F, Delussu AS, Brunelli S, Iosa M, Pellegrini R, Zenardi D, et al. The Conventional Non-Articulated SACH or a Multiaxial Prosthetic Foot for Hypomobile Transtibial Amputees? A Clinical Comparison on Mobility, Balance, and Quality of Life. ScientificWorldJournal. 2015;2015:261801. doi: 10.1155/2015/261801 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 28.Rouhani N, Esfandiari E, Babaee T, Khosravi M, Moradi V, Balouchkayvan B, et al. The comprehensive lower limb amputee socket survey: Reliability and validity of the persian version. Prosthet Orthot Int. 2021;45(2):131–7. doi: 10.1177/0309364620958526 [DOI] [PubMed] [Google Scholar]
  • 29.Ware J Jr, Kosinski M, Keller SD. A 12-Item Short-Form Health Survey: construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34(3):220–33. doi: 10.1097/00005650-199603000-00003 [DOI] [PubMed] [Google Scholar]
  • 30.Montazeri A, Vahdaninia M, Mousavi SJ, Omidvari S. The Iranian version of 12-item Short Form Health Survey (SF-12): factor structure, internal consistency and construct validity. BMC Public Health. 2009;9:341. doi: 10.1186/1471-2458-9-341 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 31.Innes E. Handgrip strength testing: A review of the literature. Aus Occup Therapy J. 1999;46(3):120–40. doi: 10.1046/j.1440-1630.1999.00182.x [DOI] [Google Scholar]
  • 32.Pallant J. SPSS survival manual. 6th ed. McGraw-Hill Education (UK). 2016. [Google Scholar]
  • 33.DadeMatthews OO, Roper JA, Vazquez A, Shannon DM, Sefton JM. Prosthetic device and service satisfaction, quality of life, and functional performance in lower limb prosthesis clients. Prosthet Orthot Int. 2024;48(4):422–30. doi: 10.1097/PXR.0000000000000285 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 34.Mohd Hawari N, Jawaid M, Md Tahir P, Azmeer RA. Case study: survey of patient satisfaction with prosthesis quality and design among below-knee prosthetic leg socket users. Disabil Rehabil Assist Technol. 2017;12(8):868–74. doi: 10.1080/17483107.2016.1269209 [DOI] [PubMed] [Google Scholar]
  • 35.Turner S, McGregor AH. Perceived Effect of Socket Fit on Major Lower Limb Prosthetic Rehabilitation: A Clinician and Amputee Perspective. Arch Rehabil Res Clin Transl. 2020;2(3):100059. doi: 10.1016/j.arrct.2020.100059 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Marks LJ, Michael JW. Science, medicine, and the future: Artificial limbs. BMJ. 2001;323(7315):732–5. doi: 10.1136/bmj.323.7315.732 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 37.Kam S, Kent M, Khodaverdian A, Daiter L, Njelesani J, Cameron D, et al. The influence of environmental and personal factors on participation of lower-limb prosthetic users in low-income countries: prosthetists’ perspectives. Disabil Rehabil Assist Technol. 2015;10(3):245–51. doi: 10.3109/17483107.2014.905643 [DOI] [PubMed] [Google Scholar]
  • 38.Alavi T, Jalali M, Farahmand B, Babaee T. Prosthesis and health-related factors of mobility in people with nontraumatic unilateral transtibial amputation. Prosthet Orthot Int. 2024;:10.1097/PXR.0000000000000378. doi: 10.1097/PXR.0000000000000378 [DOI] [PubMed] [Google Scholar]
  • 39.Manz S, Valette R, Damonte F, Avanci Gaudio L, Gonzalez-Vargas J, Sartori M, et al. A review of user needs to drive the development of lower limb prostheses. J Neuroeng Rehabil. 2022;19(1):119. doi: 10.1186/s12984-022-01097-1 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 40.Klute GK, Berge JS, Biggs W, Pongnumkul S, Popovic Z, Curless B. Vacuum-assisted socket suspension compared with pin suspension for lower extremity amputees: effect on fit, activity, and limb volume. Arch Phys Med Rehabil. 2011;92(10):1570–5. doi: 10.1016/j.apmr.2011.05.019 [DOI] [PubMed] [Google Scholar]
  • 41.Baars EC, Schrier E, Dijkstra PU, Geertzen JHB. Prosthesis satisfaction in lower limb amputees: A systematic review of associated factors and questionnaires. Medicine (Baltimore). 2018;97(39):e12296. doi: 10.1097/MD.0000000000012296 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 42.Harness N, Pinzur MS. Health related quality of life in patients with dysvascular transtibial amputation. Clin Orthop Relat Res. 2001;(383):204–7. doi: 10.1097/00003086-200102000-00023 [DOI] [PubMed] [Google Scholar]
  • 43.Van de Weg FB, Van der Windt DAWM. A questionnaire survey of the effect of different interface types on patient satisfaction and perceived problems among trans-tibial amputees. Prosthet Orthot Int. 2005;29(3):231–9. doi: 10.1080/03093640500199679 [DOI] [PubMed] [Google Scholar]
  • 44.Lathouwers E, Díaz MA, Maricot A, Tassignon B, Cherelle C, Cherelle P, et al. Therapeutic benefits of lower limb prostheses: a systematic review. J Neuroeng Rehabil. 2023;20(1):4. doi: 10.1186/s12984-023-01128-5 [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 45.Sooriakumaran S, Uden M, Mulroy S, Ewins D, Collins T. The impact a surgeon has on primary amputee prosthetic rehabilitation: A survey of residual lower limb quality. Prosthet Orthot Int. 2018;42(4):428–36. doi: 10.1177/0309364618757768 [DOI] [PubMed] [Google Scholar]

Decision Letter 0

Raffaele Vitiello

Dear Dr. Babaee,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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Academic Editor

PLOS ONE

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2. We noticed you have some minor occurrence of overlapping text with the following previous publication(s), which needs to be addressed:

https://journals.lww.com/poijournal/abstract/9900/prosthesis_and_health_related_factors_of_mobility.304.aspx

In your revision ensure you cite all your sources (including your own works), and quote or rephrase any duplicated text outside the methods section. Further consideration is dependent on these concerns being addressed.

3. We note that your Data Availability Statement is currently as follows: All relevant data are within the manuscript and in Supporting Information files.

Please confirm at this time whether or not your submission contains all raw data required to replicate the results of your study. Authors must share the “minimal data set” for their submission. PLOS defines the minimal data set to consist of the data required to replicate all study findings reported in the article, as well as related metadata and methods (https://journals.plos.org/plosone/s/data-availability#loc-minimal-data-set-definition).

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4. Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

Reviewer #1: Yes

Reviewer #2: Yes

**********

2. Has the statistical analysis been performed appropriately and rigorously? -->?>

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available??>

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Is the manuscript presented in an intelligible fashion and written in standard English??>

Reviewer #1: Yes

Reviewer #2: Yes

**********

Reviewer #1: I would like to start by thinking the authors for their work in this area. It is always important to learn about all the factors that impact quality of life for our patients with amputations.

I feel that I have only minor suggestions, which I will detail below.

Introduction

Line 77-78: The authors have a sentence starting with "Studies have indicated..." This should have a reference.

Line 105-107: The authors indicate that the focus of the study is to identify modifiable factors to enhance prosthesis rehabilitation. This is actually not what is done. They are looking at prosthesis parameters that correlate with high QofL. This may include modifications that can be implemented into the prosthesis but modifiable "factors" to enhance prosthesis rehabilitation would include modification to disease management like diabetes control as well as interventions focused on items like falls confidence, body image, mobility and balance training, community access and integration, access to education and peer support, etc. So I guess I am saying, try not to be too broad with these statements.

Methods

good

Results

good

Discussion

line 206: "Our regression analysis results revealed that the comfort subscale of CLASS is the strongest predictor of quality of life in people with non-traumatic LLA." I suggest being more specific to the study as it was in people with non-traumatic, unilateral, transtibial amputations, when looking only at prosthetic related parameters.

line 218: needs a reference

Line 221-223: There is a big assumption in the sentence "Therefore, it can be concluded that prosthetic socket comfort will increase the social interaction of ..." I recommend tempering this a bit by saying for example, ... it can be concluded that prosthetic socket comfort may increase their willingness to take part in social interactions...

Line 221-226: repetitive statements across a few sentences.

Line 262-278: Interesting discussion but the classification of articulated vs. non is unfortunately not helpful. For example an energy storage foot is not articulated but can mimic three wrockers and provide very good biomechanics in both swing and stance phase. so to lump this with a SACH would not help the reader to understand the impact of foot type. I would suggest, if able to subdivide to SACH, single axis, multi axial and Energy storage and see if there is a correlation. (if able). If not, this may be something for further study.

Limitations

okay

Conclusion:

line 307: sentence ending with "... non-traumatic LLA." I would recommend correcting to ...non-traumatic, unilateral, transtibial amputations. This is an important distinction as the authors, form this study can not generalize to bilateral amputees or transfemoral amputees or above.

Reviewer #2: The article appears to be a valuable and insightful contribution, that encompasses all available information on prosthesis-related factors that predict the quality of life in individuals with LLA, with a particular accent about modificable factors.

The results are clear and well-highlighted.

In the discussion, the role of appearance could be explored further, as the study’s findings (weak association) are only partially in line with the cited literature.

Furthermore, the section regarding the length of the residual limb could be expanded, as this is an important factor in the literature on this topic:Have other studies highlighted that the length of the residual limb does not affect quality of life?

**********

what does this mean? ). If published, this will include your full peer review and any attached files.

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Reviewer #1: No

Reviewer #2: No

**********

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PLoS One. 2025 Jul 14;20(7):e0327781. doi: 10.1371/journal.pone.0327781.r002

Author response to Decision Letter 1


31 May 2025

Journal Requirements:

1.Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

Response: We checked the PLOS ONE's style requirements and the required changes have been made in the text.

2. We noticed you have some minor occurrence of overlapping text with the following previous publication(s), which needs to be addressed:

https://journals.lww.com/poijournal/abstract/9900/prosthesis_and_health_related_factors_of_mobility.304.aspx

In your revision ensure you cite all your sources (including your own works), and quote or rephrase any duplicated text outside the methods section. Further consideration is dependent on these concerns being addressed.

Response: Thank you for your comment. In this revised version of the manuscript, we have added a sentence to the discussion that highlights the findings of our previous article, along with the corresponding citation. Additionally, we have rephrased the overlapping text to eliminate any duplicated phrases. These changes have been made using track changes.

3. We note that your Data Availability Statement is currently as follows: All relevant data are within the manuscript and in Supporting Information files.

Please confirm at this time whether or not your submission contains all raw data required to replicate the results of your study. Authors must share the “minimal data set” for their submission. PLOS defines the minimal data set to consist of the data required to replicate all study findings reported in the article, as well as related metadata and methods (https://journals.plos.org/plosone/s/data-availability#loc-minimal-data-set-definition).

For example, authors should submit the following data:

- The values behind the means, standard deviations and other measures reported;

- The values used to build graphs;

- The points extracted from images for analysis.

Authors do not need to submit their entire data set if only a portion of the data was used in the reported study.

If your submission does not contain these data, please either upload them as Supporting Information files or deposit them to a stable, public repository and provide us with the relevant URLs, DOIs, or accession numbers. For a list of recommended repositories, please see https://journals.plos.org/plosone/s/recommended-repositories.

If there are ethical or legal restrictions on sharing a de-identified data set, please explain them in detail (e.g., data contain potentially sensitive information, data are owned by a third-party organization, etc.) and who has imposed them (e.g., an ethics committee). Please also provide contact information for a data access committee, ethics committee, or other institutional body to which data requests may be sent. If data are owned by a third party, please indicate how others may request data access.

Response: The anonymized background information of participants and their questionnaire scale scores have been submitted as a supporting information file.

4. Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

Response: We used the Retraction Watch Database (https://retractionwatch.com) to search the reference list for any retractions. However, we did not identify any retracted articles. If you come across any retracted articles cited in this study, please let us know.

Reviewers' comments:

Reviewer #1: I would like to start by thinking the authors for their work in this area. It is always important to learn about all the factors that impact quality of life for our patients with amputations. I feel that I have only minor suggestions, which I will detail below.

Response: Thank you for your thorough review of our article. Your constructive comments were invaluable and greatly appreciated. We believe that your insights have significantly strengthened our work.

Comment: Line 77-78: The authors have a sentence starting with "Studies have indicated..." This should have a reference.

Response: We have now cited appropriate references for each sentence individually within the paragraph to improve clarity and attribution. These changes are highlighted in yellow in line 81 of the revised manuscript.

Comment: Line 105-107: The authors indicate that the focus of the study is to identify modifiable factors to enhance prosthesis rehabilitation. This is actually not what is done. They are looking at prosthesis parameters that correlate with high QoL. This may include modifications that can be implemented into the prosthesis but modifiable "factors" to enhance prosthesis rehabilitation would include modification to disease management like diabetes control as well as interventions focused on items like falls confidence, body image, mobility and balance training, community access and integration, access to education and peer support, etc. So I guess I am saying, try not to be too broad with these statements.

Response: Thank you for your thoughtful comment. As you correctly pointed out, the primary focus of our study is to examine how prosthetic fitting and components relate to quality of life, rather than broadly identifying all modifiable factors involved in prosthetic rehabilitation. We have revised the sentence to more accurately reflect the scope of the study. These changes can be found in lines 105–108 of the revised manuscript and are highlighted in yellow.

Comment: Discussion line 206: "Our regression analysis results revealed that the comfort subscale of CLASS is the strongest predictor of quality of life in people with non-traumatic LLA." I suggest being more specific to the study as it was in people with non-traumatic, unilateral, transtibial amputations, when looking only at prosthetic related parameters.

Response: Thank you for your attention. We have revised the sentence to better reflect our findings. The updated sentence can be found in lines 220-221 of the revised manuscript and is highlighted in yellow. Additionally, this change has been applied throughout the manuscript and is also highlighted in yellow.

Comment: line 218: needs a reference

Response: Thank you for your comment. The required reference has been added, and the change is highlighted in yellow in line 234 of the revised manuscript.

Comment: Line 221-223: There is a big assumption in the sentence "Therefore, it can be concluded that prosthetic socket comfort will increase the social interaction of ..." I recommend tempering this a bit by saying for example, ... it can be concluded that prosthetic socket comfort may increase their willingness to take part in social interactions...

Response: Thank you for your valuable suggestion. We have revised the sentence. The change is highlighted in yellow in lines 241–243 of the revised manuscript.

Comment: Line 221-226: repetitive statements across a few sentences.

Response: Thank you for your helpful feedback. As you suggested, we revised and condensed the original repetitive sentences into a more concise statement, which has been highlighted in yellow in lines 234–241 of the revised manuscript.

Comment: Line 262-278: Interesting discussion but the classification of articulated vs. non is unfortunately not helpful. For example, an energy storage foot is not articulated but can mimic three rockers and provide very good biomechanics in both swing and stance phase. so to lump this with a SACH would not help the reader to understand the impact of foot type. I would suggest, if able to subdivide to SACH, single axis, multi axial and Energy storage and see if there is a correlation. (if able). If not, this may be something for further study.

Response: Thank you for highlighting this important point. We totally agree that the function of a SACH foot is different with energy storing ones. Therefore, we have mentioned this important point in the limitation section for future studies. Please see lines 327-335.

Comment: line 307: sentence ending with "... non-traumatic LLA." I would recommend correcting to ...non-traumatic, unilateral, transtibial amputations. This is an important distinction as the authors, form this study cannot generalize to bilateral amputees or transfemoral amputees or above.

Response: Thank you for your valuable suggestion. We have revised the sentence. The change is highlighted in yellow in lines 340-341 of the revised manuscript.

Reviewer #2: Thank you for your thorough review of our article. Your constructive comments were invaluable and greatly appreciated. We believe that your insights have significantly strengthened our work.

Comment: In the discussion, the role of appearance could be explored further, as the study’s findings (weak association) are only partially in line with the cited literature.

Response: Thank you for your comment. We have added further explanation to the discussion to clarify the weak association between satisfaction with socket appearance and quality of life in our study. The updated paragraph is highlighted in yellow in lines 258-263 of the discussion section.

Comment: the section regarding the length of the residual limb could be expanded, as this is an important factor in the literature on this topic: Have other studies highlighted that the length of the residual limb does not affect quality of life?

Response: Thank you for your insightful comment. We recognize that the original paragraph may have caused some confusion regarding the source of the findings. To clarify, the discussion in this section reflects the results of our own study rather than findings from previous literature. Specifically, our study did not identify a significant correlation between residual limb length and quality of life. To the best of our knowledge, there is limited literature directly examining the relationship between residual limb length and quality of life, particularly in individuals with non-traumatic lower-limb amputation. While many studies emphasize the biomechanical and functional implications of residual limb length (including socket fit, energy expenditure, and prosthetic alignment) we were unable to locate studies that explicitly confirm or refute its influence on quality of life. Therefore, we attempted to interpret our findings within the context of known biomechanical principles and the uneven distribution of participants across residual limb length categories. We have revised the paragraph accordingly to ensure this distinction is clear. The change is highlighted in yellow in lines 298-301 of the revised manuscript.

Attachment

Submitted filename: Response to the reviewers.docx

pone.0327781.s003.docx (27.6KB, docx)

Decision Letter 1

Raffaele Vitiello

Predictors of quality of life in individuals with non-traumatic unilateral transtibial amputation

PONE-D-25-04514R1

Dear Dr. Babaee,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Raffaele Vitiello

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

Reviewer #1: All comments have been addressed

Reviewer #2: (No Response)

**********

2. Is the manuscript technically sound, and do the data support the conclusions??>

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

3. Has the statistical analysis been performed appropriately and rigorously? -->?>

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

4. Have the authors made all data underlying the findings in their manuscript fully available??>

The PLOS Data policy

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English??>

Reviewer #1: Yes

Reviewer #2: (No Response)

**********

Reviewer #1: Thank you again for your work and commitment to this population. The authors have addressed all of my comments.

Reviewer #2: (No Response)

**********

what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy

Reviewer #1: No

Reviewer #2: No

**********

Acceptance letter

Raffaele Vitiello

PONE-D-25-04514R1

PLOS ONE

Dear Dr. Babaee,

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now being handed over to our production team.

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Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Raffaele Vitiello

Academic Editor

PLOS ONE

Associated Data

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    Supplementary Materials

    S1. The values behind the means, standard deviations.

    (XLSX)

    pone.0327781.s001.xlsx (17.6KB, xlsx)
    Attachment

    Submitted filename: Response to the reviewers.docx

    pone.0327781.s003.docx (27.6KB, docx)

    Data Availability Statement

    All relevant data are within the paper and its Supporting Information files.


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