Use of Telehealth and At-Home Video for Remote Administration of the North Star Ambulatory Assessment (NSAA): A Comparative Methods Study

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Lastra, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8980113/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Remote functional assessments can expand access and reduce burden for families affected by Duchenne muscular dystrophy (DMD), but evidence is needed on the reliability of remote administration and scoring of the North Star Ambulatory Assessment (NSAA). We conducted a non-interventional, mixed‑methods study using a 21 CFR Part 11–compliant video platform to compare NSAA scores from live telehealth versus caregiver‑captured asynchronous at‑home videos and to compare live versus recorded telehealth scoring (Clinical trial number: not applicable). Eighteen participants (mean age 8.7 years) completed NSAA at baseline, 3 months, and 6 months; assessments were double‑scored by NSAA‑certified physical therapists. Mean NSAA was 25.8 (telehealth) versus 25.1 (asynchronous); the 0.82‑point difference met two one‑sided tests for equivalence within ±3‑point SEM margins (p<0.001). Live versus recorded telehealth differed by 0.23 points and was also equivalent (p<0.001). Inter‑rater mean absolute difference was 1.87 points (telehealth 1.61; asynchronous 2.15), below the MCID threshold. Remote NSAA was feasible, reliable, and clinically comparable across methods, supporting decentralized follow‑up and data collection in DMD. Figures Figure 1 Figure 2 INTRODUCTION The purpose of this non-interventional study was to evaluate the feasibility of remotely administering the North Star Ambulatory Assessment (NSAA) to participants with Duchenne muscular dystrophy (DMD) by comparing the reliability of multiple methods of administration and scoring using a clinical-trial-grade video capture platform (Red Nucleus’s iTakeControl). Duchenne Muscular Dystrophy Duchenne muscular dystrophy is a severe neuromuscular genetic disease characterized by gradual loss of motor function, respiratory failure, and cardiomyopathy due to null expression of the protein dystrophin 1 . Common early symptoms of DMD include muscle weakness and atrophy in the legs and pelvis, calf muscle hypertrophy, difficulty walking and climbing stairs, frequent falls, toe walking, shortness of breath, and developmental delay. As the disease progresses, continued skeletal muscle degeneration leads to skeletal deformities and respiratory insufficiency. Most males with DMD lose ambulation in the early teens and need assisted ventilation around 20 years of age. Ultimately, DMD causes death in early adulthood (between 20 and 40 years of age) due to respiratory insufficiency and/or cardiomyopathy 2 . The traditional standard of care includes corticosteroids to control symptoms and slow disease progression via potent anti-inflammation 3 . Alongside anti-inflammatory treatment, non-pharmacologic interventions are implemented to retain functional abilities; such interventions include physical therapy, home exercise plans, orthotics, stretching programs, and hydrotherapy 4 . More recent approaches to DMD treatment have focused directly on the dystrophin gene and expression of the dystrophin protein. In 2016, the US FDA granted accelerated approval to the first drug for DMD—an exon-skipping therapy 4 . “Exon skippers” are RNA-targeted therapies that act on messenger RNA (mRNA) during protein expression to enable production of a shortened, potentially functional dystrophin protein 6 , 7 . More recently, the FDA approved a gene therapy, delandistrogene moxeparvovec-rokl. The FDA subsequently expanded the therapy as an option for DMD patients four years or older and then, based on new safety events, restricted to ambulatory patients 9 . Additional targeted therapies for DMD are currently in development to address the unmet needs of these patients and their families 6 , 8 . The North Star Ambulatory Assessment (NSAA) The NSAA is a clinician-administered rating scale used to assess patients’ ambulatory motor function. It has been established as a suitable measure in the standard of care for DMD with determining disease progression for DMD registries and clinical trials 9 . The validity of the NSAA has been exemplified in multiple studies that establish the assessment as a reliable, clinically relevant measure of function motor ability within the DMD population that is suitable to use in research 10 . The NSAA is a 17-item rating scale that includes functional tasks such as standing, running, hopping, climbing a step, and getting up from the floor. These items assess the speed and functionality of motor skills. A 3-point scoring structure is based on the patients’ ability to perform each task as “normal,” “modified without need of assistance,” and “unable to achieve independently.” The total score can range from 0 (patient fails all items) to 34 (patient performs all activities without task modification). Previous Studies of a Remote NSAA Administration Past studies have been conducted to evaluate the ability of utilizing remote assessments and telerehabilitation for patients with DMD and other neuromuscular diseases 4 , 10 , 11 . The feasibility and reliability of completing the NSAA through telehealth channels was a focus for several studies evaluating patients with DMD. The goal of these studies was to determine if patients and their caregivers had the ability and resources to conduct telehealth or video assessments in their home, receive the same level of care, and record an accurate measure of their ambulatory status as compared to in-clinic administrations. Because in-person visits can be burdensome for DMD patients and families, especially for severe cases, telehealth or video assessment at home would alleviate some of this burden. In one recent study, pre-specified statistical analyses including intraclass correlation coefficient (ICC), Pearson, Spearman, and Bland-Altman analyses were used to measure the reproducibility of the NSAA 10-meter (10m) walk and time to rise assessments between remote and in-person administration. Eight patients completed both in-clinic and a remote assessment within two weeks of each other. Using the analyses stated, there was an ICC of 0.97, Pearson of 0.98, Spearman of 0.93 and a 95% confidence interval proving strong correlation between the two methods of administration and has clinical meaningfulness 12 . A similar study was also conducted to assess the feasibility and reliability of the NSAA by video assessment. In this study, two physiotherapists were responsible for scoring 10 ambulatory boys’ video assessments and the ICC was used to determine the similarities and differences between video scoring and previous in-clinic scores. The ICC was 0.98 for the total NSAA and 1.00 for the time to rise assessment. This study concluded that performing the NSAA through a video assessment is partially reliable and feasible; the study cited a handful of factors that may have influenced scoring (e.g., lack of control over types of flooring, difficulties confirming height of chairs and steps) 4 . Studies have also been conducted on the feasibility and reliability of video assessments for other neuromuscular diseases similar to DMD. A study was conducted to evaluate the feasibility of using Remote Study Visits (RSV) in patients with DM1. The correlation between remote assessments and patient-reported function was assessed. Out of the 23 subjects who participated, 95% completed the remote study and 91% expressed interest in participating in more remote studies in the future. This study supported feasibility of remote collection of patient-reported outcomes (PRO) and a measurable assessment for patients with DM1 13 . Forms of remote assessment other than live video sessions have included online workshops and recordings posted on the internet of online workshops where the caregiver was able to submit a picture of the patient’s posture using an app 10 . iTakeControl (iTC) Clinical Research Platform iTakeControl is a validated, video-based clinical trial platform that complies with US Code of Federal Regulations (CFR) 21 CFR Part 11. Originally deployed in 2018, iTC was designed for remote live video visits, at-home video patient-reported outcomes, traditional electronic patient reported outcomes (ePRO) evidence, and in-clinic video assessments. iTC has been used extensively in DMD and other rare disease studies using video functional assessments. Study Rationale This study aimed to build upon the previous studies by specifically testing a research-grade telehealth and video assessment platform, iTC, designed to capture clinical eCOA and PROs as well as specifically testing inter-rater reliability between NSAA rating methods. To strengthen the evidence supporting the reliability of remote NSAA administration over time, this study evaluated two distinct methods of NSAA administration: 1) Telehealth and 2) Caregiver Asynchronous At-Home Video. Additionally, we administered three scoring approaches: 1) Live Telehealth scores; 2) recorded telehealth scores; and 3) scoring of caregiver-captured asynchronous videos. Results from this study expand the body of evidence regarding the feasibility, controls, limitations, and reliability of a remote NSAA administration and illustrate the benefits and limitations of remote functional video assessments more generally. MATERIALS AND METHODS This was a noninterventional mixed methods study to evaluate three methods of remote NSAA administration. This study targeted a goal of 23 participants with DMD and their caregivers and a pool of six NSAA-certified physical therapists who performed NSAA scoring and provided study data specific to their role (“PT Raters”). A validated, 21 CFR Part 11-compliant software platform, iTC, was utilized for telehealth sessions as well as video capture and submission by caregivers of each remotely administered NSAA. The study was approved by WCG IRB (Study Number: 1358845) prior to initiating study activities. Written consent was obtained from both caregivers and participants prior to enrollment. All assessments described in this study were performed over a period of three visits over six months by qualified PT Raters in the United States in English. The following outlines the methods employed for this study, which included training materials, pre- and post-study surveys for caregivers, pre- and post-study surveys of PT raters, and a per administration evaluation by each rater after each scoring session completed. During the screening process, recruiters asked caregivers about basic background and demographic information. Once enrolled, caregivers completed surveys on two time points: pre-study (prior to the NSAA Remote Administration at enrollment) and post-study (following the second NSAA Remote Administration at the 6-month mark). PT Raters completed surveys at two time points: pre-study (prior to their first participant) and post-study (after their final participant). At each assessment timepoint, the NSAA was administered twice in a predetermined sequence based on group assignment: Participants in Group A received the Live Telehealth assessment followed by the Caregiver Asynchronous Video assessment, whereas participants in Group B received the assessments in reverse order (Caregiver Asynchronous Video followed by Live Telehealth for Group B). The rational between the two groups was to address potential learning bias and control for order effects. During the Live Telehealth session, the PT monitored for any occurrences that could result in injury during administration of the NSAA. In contrast, for the Caregiver Asynchronous Video method, caregivers could report any injury that occurred while the child was performing an NSAA task to a study monitor. A summary of the study assessment schedule is provided in Table 1. Training Materials Study-specific training materials were provided to both caregivers and PTs to orient, instruct, and establish parameters regarding how to remotely administer the NSAA using the clinical video platform. Remote NSAA administration and scoring The study evaluated three Remote NSAA Administration methods: Live Telehealth, Recorded Telehealth, and Caregiver Asynchronous Video. Participants with DMD performed all feasible 17 items on the NSAA at three timepoints: Enrollment (month 0), 3 months (±14 days), and 6 months (±14 days). At each timepoint, participants performed the NSAA tasks twice using two methods: 1) a Live Telehealth session and 2) Caregiver Asynchronous At-Home Videos. Participants were also randomly assigned to one of two sequences: Live Telehealth followed by Caregiver Asynchronous Video ( Group A ), or vice versa ( Group B ). The participant followed the assigned Group sequence at all three timepoints with a minimum 48‑hour recovery period between administrations. For each timepoint, each participant had a total of four NSAA scores from a total of three PT Raters (see Figure 1 ). To add validity to the comparison between methods (Live Telehealth and Caregiver Asynchronous Video), each NSAA administration was scored by two different PT Raters. Wherever feasible, remote NSAA administration was designed to mirror the functional tasks, instructions, and best practices of the in-person protocol. Any deviations from standard in-clinic procedures were systematically documented to support equivalency and ensure scoring. This approach was intended to preserve the interpretive integrity of NSAA scores. For example, accommodations made to reduce caregiver and participant burden, or to adapt to specific home environments (e.g., flooring type) were permitted provided the PT experts determined such modifications would not impact the functional scoring of performance. Live Telehealth A PT Rater was present during each Live Telehealth session. While the caregiver captured video of the participant performing NSAA tasks via the video platform, the PT Rater remotely administered the NSAA in real time, providing instructions and observing performance. The PT Rater then scored the participant’s performance of each NSAA task as Rater #1 during the session. All sessions were recorded in full to support subsequent review and scoring. Recorded Telehealth Score This Recorded Telehealth session video was then subsequently scored in the platform by a different PT as Rater #2 to yield the Recorded Telehealth Score . Caregiver Asynchronous Video In contrast to the telehealth session, no PT was present for the Caregiver Asynchronous At-Home Video sessions. For this method, the participant was instructed to perform the NSAA tasks by their caregiver and the caregiver used the platform’s mobile app to record and submit video of the participant’s NSAA items. Once the video was submitted to the platform, the participant’s NSAA performance was scored separately by two different PT Raters (Rater #2 and Rater #3). Caregiver Surveys The study incorporated caregiver surveys to evaluate the qualitative experience of remote NSAA administration. Surveys were administered at two timepoints: pre-study (prior to the first NSAA session) and post-study (following the final NSAA session at six months). The pre-study survey captured caregiver familiarity with the NSAA, comfort with smartphone and software use, expectations regarding telehealth, and internet access. The post-study survey gathered feedback on each remote administration method, the clarity and utility of training materials, and overall experience with the software platform. These data were intended to inform the feasibility, acceptability, and user-centered design of remote NSAA protocols. PT Rater Evaluation Forms and Surveys PT Raters participated in both pre-study and post-study surveys to capture their perceptions and experiences with remote NSAA administration. Additionally, following each NSAA administration (whether conducted live via telehealth or scored asynchronously), each PT Rater completed a Remote NSAA Method Evaluation Form. This form was designed to assess key aspects of each administration method, including reliability, accuracy, and feasibility therefore contributing to the study’s evaluation of methodological consistency and practical implementation. Code Availability The R code used for statistical analyses in this study is not publicly available due to its integration with restricted datasets. The code may be made available to qualified researchers upon reasonable request from the corresponding author. RESULTS Demographics A total of 18 caregiver and participant pairs completed the study. The mean age of the 18 Duchenne participants was 8.7, ranging from 6 to 12 years. See Table 2 for Final Participant Demographics. See Table 3 for Final Caregiver Demographics. Primary Outcomes: Administration and Scoring Methods The primary objective of this study was to evaluate the reliability and comparability of three remote NSAA administration methods: Live Telehealth, Recorded Telehealth, and Asynchronous Caregiver Video - each independently scored by PTs using video recordings, as an alternative to traditional, in-clinic NSAA administration. NSAA scores obtained via Asynchronous and Telehealth administration methods were highly similar. The mean (and standard deviation) for Asynchronous NSAA scores was 25.1 (4.99) and 25.8 (5.48) for Telehealth assessments (see Table 4). Although Telehealth scores were on average 0.7 points higher than Asynchronous scores when comparing overall means, this difference was well below the published minimal clinically important difference (MCID) and the standard error of measurement (SEM) for the NSAA 9 . In supportive analyses (see Table 5), paired equivalence testing showed that Telehealth and Asynchronous scores fell within SEM-based equivalence margins (equivalence p < 0.001 for all comparisons). These findings support clinical comparability between administration methods while acknowledging a small systematic difference that was not clinically meaningful. Scores were also highly similar between the scoring methods of the Telehealth administration of the NSAA, with live scoring (26.1 [5.67]) resulting in a 0.6 point (2.3%) higher score on average than scoring of the recorded Telehealth session (25.5 [5.54]). In supportive paired analyses, Live and Recorded Telehealth scores were observed to fall within both MCID- and SEM-based equivalence margins, supporting the robustness of Telehealth scoring regardless of whether assessments were scored in real-time or from recorded sessions. Mean NSAA scores were similar across the three assessment windows, Baseline, 3-Month, and 6-Month. The mean NSAA score at Baseline and 3-Month was identical (25.4 , with a negligible increase at Month 6 (25.5). These values represent combined Asynchronous and Telehealth assessment scores, with no clinically meaningful differences observed across assessment windows. The NSAA scores were consistent between raters within each NSAA scoring assignment, regardless of the scoring method . The mean absolute difference (and standard deviation) between the two rater scores across all scoring methods was 1.87 (1.52). Inter-rater agreement was high across all scoring methods. The mean absolute difference between paired rater scores for all NSAA assessments was 1.87 (1.52) points. Inter-rater differences were slightly greater for Asynchronous assessments (2.15 [1.75] points) compared with Telehealth assessments (1.61 [1.22] points).All observed rater differences remained below established MCID and SEM thresholds, indicating acceptable agreement regardless of administration modality. Secondary Outcomes: 1. Rater Experience Overall, the 6 raters (see Figure 2) demonstrated increased confidence in their personal ability to administer and score the NSAA using telehealth and video technology over the approximate 15-month period between the pre- and post-surveys. Their perceptions of telehealth as a viable tool for outcomes assessments as well as their belief in the feasibility of completing the NSAA effectively via telehealth also improved during this time. Additionally, raters reported greater comfort with administering the NSAA via telehealth in the post survey compared to pre-survey. Please see Table 6 for final rater demographics. 2. Caregiver Experience At the conclusion of the study, a majority of caregivers preferred in-person or indicated no preference, when asked whether they had a preference for administrative methods to capture the NSAA (specifically: “ As the caregiver, how would you prefer to participate in routine mobility or activity assessments like the NSAA (e.g., walking or steps) conducted by a Physical Therapist? ”). Overall, there was only a modest change from pre- to post study preferences. Please see Table 7 for the caregiver-preferred setting of assessment breakdown and Table 8 for reasons expressed when in-person at clinic was preferred. Given perceived burdens for In Person visits, we also consider this counter-intuitive data further in the Discussion section. 3. Training Material Feedback from Caregivers Overall, a large majority of caregivers found the training materials and instructions to be helpful and easy to understand for remote NSAA administration using telehealth and video technology. When considering the training videos viewed within the mobile application, 88% of caregivers found the videos to be easy to understand and helpful with guiding the performance of the NSAA activities. Additionally, 94% of caregivers did not think there were areas where the training videos could be improved. When considering the caregiver manual, 94% of caregivers found the manual easy to understand while 100% found it helpful in guiding the performance of the NSAA activities. Although the positive response rate fell just short of 100%, the difference was accounted for entirely by neutral responses; importantly, no respondents indicated that the materials were difficult to understand or unhelpful. 4. Data Availability The datasets generated and/or analyzed during the current study are anonymized but not publicly available due to privacy and ethical considerations, including the potential risk of de-identification. Data are available from the corresponding author on reasonable request. DISCUSSION In the context of rare disease research, the number of treated patients is typically small. This constraint raises the critical importance of long term follow up, post-approval confirmatory studies, outcomes registries, and generating data across the disease population and individual patients. For affected patients and their families, tracking outcomes and longitudinal changes is essential for understanding disease progression relative to natural history. While this need is recognized, it presents ongoing challenges and burdens for clinicians and patients alike. Consequently, the identification, evaluation and validation of innovative clinical follow up methodologies are imperative to ensure the collection of key follow up measures while minimizing the burden for families. This study contributes to the growing body of literature on remote administration of neuromuscular clinical outcomes assessments by validating and extending insights into the performance of the NSAA in home settings. The effectiveness of training materials, the feasibility of PT-led telehealth and caregiver-led at-home collection, and the consistent and reliable scoring of outcomes collectively demonstrate that NSAA remote administration is feasible and reliable. These findings have important implications for expanding access, reducing travel burden, and increasing flexibility for families engaged in ongoing clinical monitoring. Nonetheless, it is essential to acknowledge that caregiver and principal investigator (PI) preferences may vary, and some families may benefit from or prefer in-clinic assessments. Therefore, future post-approval implementation strategies should, where possible, consider designing with flexibility in mind, allowing for both remote and in-person options tailored to individual family circumstances, technological capabilities, and clinical requirements. The most notable finding of this study is the demonstrated accuracy, consistency, and reliability of the remote NSAA scoring. The involvement of multiple raters and assessment methods yielded results within the established margin of error for the NSAA. Based on these outcomes, we suggest that sponsors, regulators, payers, clinical personnel, and patients and their families can confidently consider remote administration and scoring provided that appropriate training, monitoring, and oversight mechanisms are put in place. The difference in mean scores between Asynchronous and Telehealth scoring methods (0.7 points), the difference between recorded and live Telehealth (0.6 points), and the mean difference between individual rater scores of all scoring methods (1.87 points) are all less than the NSAA’s published minimal clinically important difference of 2.3–2.9 (or 6.5–8.2 depending on the approach) or the standard error of measure of 2.9–3.5. The mean difference between the two raters utilizing the Telehealth scoring method may have been smaller due to the ability to have the participant perform an item again or at a different angle to have a better look to better discern between item scores, where as the Asynchronous scoring method only provided the angles or attempts which the caregiver provided/captured, and the raters did not have a chance to improve a viewing angle to more accurately score. Regarding the finding that the live scoring resulted in a 0.6 point higher score on average when compared to the scoring of the recorded telehealth sessions, this difference may be due to the rater’s ability to watch the recording zoomed in and/or at different speeds and thus analyze movements patterns more specifically and accurately. Caregiver responses to the training materials, along with the high compliance rate of submitted videos as reviewed by the study’s data management team further support the robustness of remote NSAA administration Notably, only 9/1071 (~ 1%) of all study videos were missed/non-compliant with the NSAA protocol. Regarding the raters’ experience, the observed increased from pre- to post-study provides additional evidence in favor of adopting remote NSAA methodologies. Sponsors, PTs, and study personnel should prioritize comprehensive training and rigorous oversight to ensure the reliability and integrity of remote assessments. An unexpected finding in this study was the inconsistency between caregivers’ stated preferences for assessment settings and their responses to the caregiver surveys. While a majority indicated a preference for telehealth or expressed no strong preference when asked directly, their survey responses revealed more nuanced attitudes, including concerns about technology reliability, comfort with remote interactions, and perceptions of accuracy of remote assessments. This discrepancy suggests that caregiver preferences may be context-dependent and influenced by factors such as prior experience, child-specific needs, and logistical considerations. This finding highlights the importance of offering flexible assessment options and engaging caregivers in an ongoing dialogue to ensure that chosen approaches align with evolving needs and expectations. While perhaps counter-intuitive of having the setting be performed consistently, the literature and this study’s data support the notion that the NSAA can be accurately scored in clinic and at home settings with accuracy. Being able to reference this study may help improve a caregiver’s confidence in the accuracy of remote assessments. We would also note that the Caregiver survey did not address the dimension of time. For example, preferences were not explored in the context of long-term clinical outcome extension study, such as those which required over a duration of a 5-to-10-year period in gene therapy or other rare disease follow-up scenarios. This temporal aspect may significantly influence caregiver preferences and warrants further investigation. A limitation of this study is its exclusive use of remote administration methods, without a direct comparison to in-clinic assessments. Consequently, while the findings support the feasibility and acceptability of telehealth for administering the NSAA, they do not provide insight into how remote assessments may differ in accuracy, reliability, or caregiver/rater preference when compared to traditional in-person evaluations. However, Researchers are encouraged to refer to the work of Linda Lowes and colleagues, who conducted comparative studies addressing these dimensions. Further research incorporating a randomized or crossover design comparing remote and in-clinic NSAA administration would continue to add to the evidence and understanding on the relative. Declarations Human Ethics and Consent to Participate: This study was conducted in accordance with the principles of the Declaration of Helsinki. Approval was granted by WCG IRB (Study Number: 1358845) prior to initiating study activities. Written informed consent was obtained from both caregivers and participants prior to enrollment. Competing Interests: James D. Lastra, Julia Dailey Gothier, and Christopher Jones are employees of Red Nucleus, which owns the technology platform (iTakeControl) used in this study. These 3 authors are salaried employees and did not receive additional compensation related to this research. Red Nucleus received research funding from Pfizer, Inc. for the conduct of this study. Anna Stachel Kane and Nathaniel Posner are employees and shareholders of Pfizer, Inc. The remaining authors declare no conflicts of interest. Funding: This study was funded by Pfizer, Inc. and conducted by Red Nucleus. Pfizer contributed to the study design but was not involved in study conduct or data analysis. Red Nucleus performed all data acquisition and analyses. Results were shared with Pfizer after analysis was completed. Consent for Publication: Not applicable. Authors’ Contributions: A.S.K, N.F., E.C.L., and C.J. wrote the main manuscript text. A.S.K, N.F., E.C.L., J.D.L., N.P., and C.J. made substantial contributions to the design of the study and interpretation of the data. J.D.L and J.D.G. made substantial contributions to the acquisition and analysis of the data, wrote the main body of the results section, and created all tables and figures. All authors reviewed the manuscript and approved the submitted version. All authors have agreed to be both personally accountable for the author's own contributions and to ensure that questions related to the accuracy or integrity of any part of the work, even ones in which the author was not personally involved, are appropriately investigated, resolved, and the resolution documented in the literature. Acknowledgements: The authors acknowledge Nic Valle, Katie Vetro, Amanda Long, Grace Kalala, and Jane Fiordeliso (Red Nucleus) for their contributions to the technology platform, study conduct, and data acquisition. References Nowak KJ, Davies KE. 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Wien Klin Wochenschr. 2021;133:344–350. doi:10.1007/s00508-020-01786-8 Tanner K, Bican R, Boster J, et al. Feasibility and acceptability of clinical pediatric telerehabilitation services. Int J Telerehabil. 2020;12(2):43‑52. doi:10.5195/ijt.2020.6336 Tables Tables 1 to 8 are available in the supplementary files section Additional Declarations Competing interest reported. James D. Lastra, Julia Dailey Gothier, and Christopher Jones are employees of Red Nucleus, which owns the technology platform (iTakeControl) used in this study. These 3 authors are salaried employees and did not receive additional compensation related to this research. Red Nucleus received research funding from Pfizer, Inc. for the conduct of this study. Anna Stachel Kane and Nathaniel Posner are employees and shareholders of Pfizer, Inc. The remaining authors declare no conflicts of interest. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8980113","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":617844694,"identity":"49391bb2-f012-4f03-a169-29fc8a8875c6","order_by":0,"name":"Anna Stachel Kane","email":"","orcid":"","institution":"Pfizer (United States)","correspondingAuthor":false,"prefix":"","firstName":"Anna","middleName":"Stachel","lastName":"Kane","suffix":""},{"id":617844695,"identity":"8169c127-8c6b-4b81-b124-41314c215ffb","order_by":1,"name":"Nathan Foreman","email":"","orcid":"","institution":"RehabMetrics","correspondingAuthor":false,"prefix":"","firstName":"Nathan","middleName":"","lastName":"Foreman","suffix":""},{"id":617844697,"identity":"869daead-39ac-49b6-bfe1-8dc37598c434","order_by":2,"name":"Emily Case Lazzaro","email":"","orcid":"","institution":"RehabMetrics","correspondingAuthor":false,"prefix":"","firstName":"Emily","middleName":"Case","lastName":"Lazzaro","suffix":""},{"id":617844701,"identity":"a70717ca-dd4d-43f1-875b-0bdc66d46827","order_by":3,"name":"James D. Lastra","email":"","orcid":"","institution":"Red Nucleus Yardley","correspondingAuthor":false,"prefix":"","firstName":"James","middleName":"D.","lastName":"Lastra","suffix":""},{"id":617844702,"identity":"3dc3cd00-0ae3-4a0f-abe9-6e13580c9680","order_by":4,"name":"Julia Dailey Gothier","email":"","orcid":"","institution":"Red Nucleus Yardley","correspondingAuthor":false,"prefix":"","firstName":"Julia","middleName":"Dailey","lastName":"Gothier","suffix":""},{"id":617844705,"identity":"581e5826-6d6e-4370-867c-20a5b06173c0","order_by":5,"name":"Nathaniel Posner","email":"","orcid":"","institution":"Pfizer (United States)","correspondingAuthor":false,"prefix":"","firstName":"Nathaniel","middleName":"","lastName":"Posner","suffix":""},{"id":617844710,"identity":"1e393829-30f0-4015-91d5-f28eb5705da6","order_by":6,"name":"Christopher Jones","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABCElEQVRIiWNgGAWjYDACCTB5gIGxAURX2MiBuQ8IaTkA13ImzRisJYEYLWDA2HY4EawVnxb+2b2PP3/ccSefub334MOfbYfT54cdfgi0xU5OtwGHJXeOm0kcPPPMsrHnXLIxz7n03I230wyAWpKNzQ5g12IgkcbGcLDtsAHjjBwzaYYy69yNsxNAWg4kbsOthfkDVIv5zx9szOmGs9M/ENLCIAGzhYGnzTlBXjoHvy0SN9LYJM6eAWrpOWMszXMmzXCDdE7BgQQD3H7hnwF0WOWOwwaG7T2GH39U2MjLz07f/OFDhZ0cLi1gAIpGwwaYU8EqDfAoh2mRh3HkG3ArHAWjYBSMgpEJAEMVaZVBvYNdAAAAAElFTkSuQmCC","orcid":"","institution":"Red Nucleus Yardley","correspondingAuthor":true,"prefix":"","firstName":"Christopher","middleName":"","lastName":"Jones","suffix":""}],"badges":[],"createdAt":"2026-02-26 16:53:12","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8980113/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8980113/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":106311287,"identity":"c73d7e40-619b-4c83-846e-3db39cbee7f4","added_by":"auto","created_at":"2026-04-07 10:28:53","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":121017,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eGroup A Rater Schedule\u003c/em\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-8980113/v1/0f96ed7722ae3b21adf8e957.png"},{"id":106311268,"identity":"5bb7d9b0-d373-4c7f-b66f-d6f24b626a0e","added_by":"auto","created_at":"2026-04-07 10:28:53","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":433749,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cem\u003eRater Survey Responses\u003c/em\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-8980113/v1/2c0d2dd47f5b25b550663f81.png"},{"id":106403830,"identity":"f4e2af83-e15b-409b-8dae-29f405a259b1","added_by":"auto","created_at":"2026-04-08 09:15:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1292452,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8980113/v1/42c5f492-2f2d-4195-9c9b-3efebc23a368.pdf"},{"id":106311269,"identity":"d2f41950-af0a-4797-9e95-7090f55d7017","added_by":"auto","created_at":"2026-04-07 10:28:53","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":22566,"visible":true,"origin":"","legend":"","description":"","filename":"Tables.docx","url":"https://assets-eu.researchsquare.com/files/rs-8980113/v1/8611cfc8b827dd55c4723ff6.docx"}],"financialInterests":"Competing interest reported. James D. Lastra, Julia Dailey Gothier, and Christopher Jones are employees of Red Nucleus, which owns the technology platform (iTakeControl) used in this study. These 3 authors are salaried employees and did not receive additional compensation related to this research. Red Nucleus received research funding from Pfizer, Inc. for the conduct of this study. Anna Stachel Kane and Nathaniel Posner are employees and shareholders of Pfizer, Inc. The remaining authors declare no conflicts of interest.","formattedTitle":"Use of Telehealth and At-Home Video for Remote Administration of the North Star Ambulatory Assessment (NSAA): A Comparative Methods Study","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003e The purpose of this non-interventional study was to evaluate the feasibility of remotely administering the North Star Ambulatory Assessment (NSAA) to participants with Duchenne muscular dystrophy (DMD) by comparing the reliability of multiple methods of administration and scoring using a clinical-trial-grade video capture platform (Red Nucleus\u0026rsquo;s iTakeControl).\u003c/p\u003e \u003cp\u003eDuchenne Muscular Dystrophy\u003c/p\u003e \u003cp\u003eDuchenne muscular dystrophy is a severe neuromuscular genetic disease characterized by gradual loss of motor function, respiratory failure, and cardiomyopathy due to null expression of the protein dystrophin\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Common early symptoms of DMD include muscle weakness and atrophy in the legs and pelvis, calf muscle hypertrophy, difficulty walking and climbing stairs, frequent falls, toe walking, shortness of breath, and developmental delay. As the disease progresses, continued skeletal muscle degeneration leads to skeletal deformities and respiratory insufficiency. Most males with DMD lose ambulation in the early teens and need assisted ventilation around 20 years of age. Ultimately, DMD causes death in early adulthood (between 20 and 40 years of age) due to respiratory insufficiency and/or cardiomyopathy\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe traditional standard of care includes corticosteroids to control symptoms and slow disease progression via potent anti-inflammation\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. Alongside anti-inflammatory treatment, non-pharmacologic interventions are implemented to retain functional abilities; such interventions include physical therapy, home exercise plans, orthotics, stretching programs, and hydrotherapy\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. More recent approaches to DMD treatment have focused directly on the dystrophin gene and expression of the dystrophin protein. In 2016, the US FDA granted accelerated approval to the first drug for DMD\u0026mdash;an exon-skipping therapy\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. \u0026ldquo;Exon skippers\u0026rdquo; are RNA-targeted therapies that act on messenger RNA (mRNA) during protein expression to enable production of a shortened, potentially functional dystrophin protein \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. More recently, the FDA approved a gene therapy, delandistrogene moxeparvovec-rokl. The FDA subsequently expanded the therapy as an option for DMD patients four years or older and then, based on new safety events, restricted to ambulatory patients\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. Additional targeted therapies for DMD are currently in development to address the unmet needs of these patients and their families\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe North Star Ambulatory Assessment (NSAA)\u003c/p\u003e \u003cp\u003eThe NSAA is a clinician-administered rating scale used to assess patients\u0026rsquo; ambulatory motor function. It has been established as a suitable measure in the standard of care for DMD with determining disease progression for DMD registries and clinical trials\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. The validity of the NSAA has been exemplified in multiple studies that establish the assessment as a reliable, clinically relevant measure of function motor ability within the DMD population that is suitable to use in research \u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe NSAA is a 17-item rating scale that includes functional tasks such as standing, running, hopping, climbing a step, and getting up from the floor. These items assess the speed and functionality of motor skills. A 3-point scoring structure is based on the patients\u0026rsquo; ability to perform each task as \u0026ldquo;normal,\u0026rdquo; \u0026ldquo;modified without need of assistance,\u0026rdquo; and \u0026ldquo;unable to achieve independently.\u0026rdquo; The total score can range from 0 (patient fails all items) to 34 (patient performs all activities without task modification).\u003c/p\u003e \u003cp\u003ePrevious Studies of a Remote NSAA Administration\u003c/p\u003e \u003cp\u003ePast studies have been conducted to evaluate the ability of utilizing remote assessments and telerehabilitation for patients with DMD and other neuromuscular diseases\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. The feasibility and reliability of completing the NSAA through telehealth channels was a focus for several studies evaluating patients with DMD. The goal of these studies was to determine if patients and their caregivers had the ability and resources to conduct telehealth or video assessments in their home, receive the same level of care, and record an accurate measure of their ambulatory status as compared to in-clinic administrations. Because in-person visits can be burdensome for DMD patients and families, especially for severe cases, telehealth or video assessment at home would alleviate some of this burden.\u003c/p\u003e \u003cp\u003eIn one recent study, pre-specified statistical analyses including intraclass correlation coefficient (ICC), Pearson, Spearman, and Bland-Altman analyses were used to measure the reproducibility of the NSAA 10-meter (10m) walk and time to rise assessments between remote and in-person administration. Eight patients completed both in-clinic and a remote assessment within two weeks of each other. Using the analyses stated, there was an ICC of 0.97, Pearson of 0.98, Spearman of 0.93 and a 95% confidence interval proving strong correlation between the two methods of administration and has clinical meaningfulness\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eA similar study was also conducted to assess the feasibility and reliability of the NSAA by video assessment. In this study, two physiotherapists were responsible for scoring 10 ambulatory boys\u0026rsquo; video assessments and the ICC was used to determine the similarities and differences between video scoring and previous in-clinic scores. The ICC was 0.98 for the total NSAA and 1.00 for the time to rise assessment. This study concluded that performing the NSAA through a video assessment is partially reliable and feasible; the study cited a handful of factors that may have influenced scoring (e.g., lack of control over types of flooring, difficulties confirming height of chairs and steps)\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eStudies have also been conducted on the feasibility and reliability of video assessments for other neuromuscular diseases similar to DMD. A study was conducted to evaluate the feasibility of using Remote Study Visits (RSV) in patients with DM1. The correlation between remote assessments and patient-reported function was assessed. Out of the 23 subjects who participated, 95% completed the remote study and 91% expressed interest in participating in more remote studies in the future. This study supported feasibility of remote collection of patient-reported outcomes (PRO) and a measurable assessment for patients with DM1\u003csup\u003e13\u003c/sup\u003e. Forms of remote assessment other than live video sessions have included online workshops and recordings posted on the internet of online workshops where the caregiver was able to submit a picture of the patient\u0026rsquo;s posture using an app\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eiTakeControl (iTC) Clinical Research Platform\u003c/p\u003e \u003cp\u003eiTakeControl is a validated, video-based clinical trial platform that complies with US Code of Federal Regulations (CFR) 21 CFR Part 11. Originally deployed in 2018, iTC was designed for remote live video visits, at-home video patient-reported outcomes, traditional electronic patient reported outcomes (ePRO) evidence, and in-clinic video assessments. iTC has been used extensively in DMD and other rare disease studies using video functional assessments.\u003c/p\u003e \u003cp\u003eStudy Rationale\u003c/p\u003e \u003cp\u003eThis study aimed to build upon the previous studies by specifically testing a research-grade telehealth and video assessment platform, iTC, designed to capture clinical eCOA and PROs as well as specifically testing inter-rater reliability between NSAA rating methods.\u003c/p\u003e \u003cp\u003eTo strengthen the evidence supporting the reliability of remote NSAA administration over time, this study evaluated two distinct methods of NSAA administration: 1) Telehealth and 2) Caregiver Asynchronous At-Home Video. Additionally, we administered three scoring approaches: 1) Live Telehealth scores; 2) recorded telehealth scores; and 3) scoring of caregiver-captured asynchronous videos.\u003c/p\u003e \u003cp\u003eResults from this study expand the body of evidence regarding the feasibility, controls, limitations, and reliability of a remote NSAA administration and illustrate the benefits and limitations of remote functional video assessments more generally.\u003c/p\u003e"},{"header":"MATERIALS AND METHODS","content":"\u003cp\u003eThis was a noninterventional mixed methods study to evaluate three methods of remote NSAA administration. This study targeted a goal of 23\u0026nbsp;participants with DMD and their caregivers and a pool of six NSAA-certified physical therapists who performed NSAA scoring and provided study data specific to their role (\u0026ldquo;PT Raters\u0026rdquo;). A validated, 21\u0026nbsp;CFR\u0026nbsp;Part\u0026nbsp;11-compliant software platform, iTC, was utilized for telehealth sessions as well as video capture and submission by caregivers of each remotely administered NSAA.\u003c/p\u003e\n\u003cp\u003eThe study was approved by WCG IRB (Study Number: 1358845) prior to initiating study activities. Written consent was obtained from both caregivers and participants prior to enrollment.\u003c/p\u003e\n\u003cp\u003eAll assessments described in this study were performed over a period of three visits over six months by qualified PT Raters in the United States in English. The following outlines the methods employed for this study, which included training materials, pre- and post-study surveys for caregivers, pre- and post-study surveys of PT raters, and a per administration evaluation by each rater after each scoring session completed.\u003c/p\u003e\n\u003cp\u003eDuring the screening process, recruiters asked caregivers about basic background and demographic information. Once enrolled, caregivers completed surveys on two time points: pre-study (prior to the NSAA Remote Administration at enrollment) and post-study (following the second NSAA Remote Administration at the 6-month mark).\u003c/p\u003e\n\u003cp\u003ePT Raters completed surveys at two time points: pre-study (prior to their first participant) and post-study (after their final participant).\u003c/p\u003e\n\u003cp\u003eAt each assessment timepoint, the NSAA was administered twice in a predetermined sequence based on group assignment: Participants in Group A received the Live Telehealth assessment followed by the Caregiver Asynchronous Video assessment, whereas participants in Group B received the assessments in reverse order (Caregiver Asynchronous Video followed by Live Telehealth for Group B). The rational between the two groups was to address potential learning bias and control for order effects.\u003c/p\u003e\n\u003cp\u003eDuring the Live Telehealth session, the PT monitored for any occurrences that could result in injury during administration of the NSAA. In contrast, for the Caregiver Asynchronous Video method, caregivers could report any injury that occurred while the child was performing an NSAA task to a study monitor.\u003c/p\u003e\n\u003cp\u003eA summary of the study assessment schedule is provided in \u003cem\u003eTable 1.\u003c/em\u003e\u003c/p\u003e\n\u003ch2\u003eTraining Materials\u003c/h2\u003e\n\u003cp\u003eStudy-specific training materials were provided to both caregivers and PTs to orient, instruct, and establish parameters regarding how to remotely administer the NSAA using the clinical video platform.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003eRemote NSAA administration and scoring\u003c/h2\u003e\n\u003cp\u003eThe study evaluated three Remote NSAA Administration methods: Live Telehealth, Recorded Telehealth, and Caregiver Asynchronous Video. Participants with DMD performed all feasible 17 items on the NSAA at three timepoints: \u003cstrong\u003eEnrollment\u003c/strong\u003e (month 0), \u003cstrong\u003e3\u0026nbsp;months\u003c/strong\u003e (\u0026plusmn;14 days), and \u003cstrong\u003e6\u0026nbsp;months\u003c/strong\u003e (\u0026plusmn;14 days). At each timepoint, participants performed the NSAA tasks twice using two methods: 1) a Live Telehealth session and 2) Caregiver Asynchronous At-Home Videos.\u003c/p\u003e\n\u003cp\u003eParticipants were also randomly assigned to one of two sequences: Live Telehealth followed by Caregiver Asynchronous Video (\u003cstrong\u003eGroup\u0026nbsp;A\u003c/strong\u003e), or vice versa (\u003cstrong\u003eGroup\u0026nbsp;B\u003c/strong\u003e). The participant followed the assigned Group sequence at all three timepoints with a minimum 48‑hour recovery period between administrations.\u003c/p\u003e\n\u003cp\u003eFor each timepoint, each participant had a total of four NSAA scores from a total of three PT Raters (see \u003cem\u003eFigure 1\u003c/em\u003e). To add validity to the comparison between methods \u0026nbsp;(Live Telehealth and Caregiver Asynchronous Video), each NSAA administration was scored by two different PT Raters.\u003c/p\u003e\n\u003cp\u003eWherever feasible, remote NSAA administration was designed to mirror the functional tasks, instructions, and best practices of the in-person protocol. Any deviations from standard in-clinic procedures were systematically documented to support equivalency and ensure scoring. This approach was intended to preserve the interpretive integrity of NSAA scores. For example, accommodations made to reduce caregiver and participant burden, or to adapt to specific home environments (e.g., flooring type) were permitted provided the PT experts determined such modifications would not impact the functional scoring of performance.\u003c/p\u003e\n\u003ch2 id=\"_Toc135747785\"\u003eLive Telehealth\u003c/h2\u003e\n\u003cp\u003eA PT Rater was present during each \u003cstrong\u003eLive Telehealth\u0026nbsp;\u003c/strong\u003esession. While the caregiver captured video of the participant performing NSAA tasks via the video platform, the PT Rater remotely administered the NSAA in real time, providing instructions and observing performance. The PT Rater then scored the participant\u0026rsquo;s performance of each NSAA task as Rater\u0026nbsp;#1 during the session. All sessions were recorded in full to support subsequent review and scoring.\u003c/p\u003e\n\u003ch2\u003eRecorded Telehealth Score\u003c/h2\u003e\n\u003cp\u003eThis Recorded Telehealth\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003esession video was then subsequently scored in the platform by a different PT as Rater #2 to yield the \u003cstrong\u003eRecorded Telehealth Score\u003c/strong\u003e.\u003c/p\u003e\n\u003ch2 id=\"_Toc135747786\"\u003eCaregiver Asynchronous Video\u003c/h2\u003e\n\u003cp\u003eIn contrast to the telehealth session, no PT was present for the \u003cstrong\u003eCaregiver Asynchronous At-Home Video\u003c/strong\u003e sessions. For this method, the participant was instructed to perform the NSAA tasks by their caregiver and the caregiver used the platform\u0026rsquo;s mobile app to record and submit video of the participant\u0026rsquo;s NSAA items. Once the video was submitted to the platform, the participant\u0026rsquo;s NSAA performance was scored separately by two different PT Raters (Rater #2 and Rater #3).\u003c/p\u003e\n\u003ch2 id=\"_Toc135747788\"\u003eCaregiver Surveys\u003c/h2\u003e\n\u003cp\u003eThe study incorporated caregiver surveys to evaluate the qualitative experience of remote NSAA administration. Surveys were administered at two timepoints: pre-study (prior to the first NSAA session) and post-study (following the final NSAA session at six months). The pre-study survey captured caregiver familiarity with the NSAA, comfort with smartphone and software use, expectations regarding telehealth, and internet access. The post-study survey gathered feedback on each remote administration method, the clarity and utility of training materials, and overall experience with the software platform. These data were intended to inform the feasibility, acceptability, and user-centered design of remote NSAA protocols.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003ePT Rater Evaluation Forms and Surveys\u003c/h2\u003e\n\u003cp\u003ePT Raters participated in both pre-study and post-study surveys to capture their perceptions and experiences with remote NSAA administration. Additionally, following each NSAA administration (whether conducted live via telehealth or scored asynchronously), each PT Rater completed a \u003cstrong\u003eRemote NSAA Method Evaluation Form.\u003c/strong\u003e This form was designed to assess key aspects of each administration method, including reliability, accuracy, and feasibility therefore contributing to the study\u0026rsquo;s evaluation of methodological consistency and practical implementation.\u003c/p\u003e\n\u003ch2\u003eCode Availability\u003c/h2\u003e\n\u003cp\u003eThe R code used for statistical analyses in this study is not publicly available due to its integration with restricted datasets. The code may be made available to qualified researchers upon reasonable request from the corresponding author.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003ch2\u003eDemographics\u003c/h2\u003e\n\u003cp\u003eA total of 18 caregiver and participant pairs completed the study. The mean age of the 18 Duchenne participants was 8.7, ranging from 6 to 12 years. See\u003cem\u003e\u0026nbsp;Table 2\u0026nbsp;\u003c/em\u003efor Final Participant Demographics. See \u003cem\u003eTable 3\u003c/em\u003e for Final Caregiver Demographics.\u0026nbsp;\u003c/p\u003e\n\u003ch2\u003ePrimary Outcomes: Administration and Scoring Methods\u003c/h2\u003e\n\u003cp\u003eThe primary objective of this study was to evaluate the reliability and comparability of three remote NSAA administration methods: Live Telehealth, Recorded Telehealth, and Asynchronous Caregiver Video - each independently scored by PTs using video recordings, as an alternative to traditional, in-clinic NSAA administration.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNSAA scores obtained via Asynchronous and Telehealth \u003cstrong\u003eadministration methods\u003c/strong\u003e were highly similar. The mean (and standard deviation) for Asynchronous NSAA scores was 25.1 (4.99) and 25.8 (5.48) for Telehealth assessments (see \u003cem\u003eTable 4).\u0026nbsp;\u003c/em\u003eAlthough Telehealth scores were on average 0.7 points higher than Asynchronous scores when comparing overall means, this difference was well below the published minimal clinically important difference (MCID) and the standard error of measurement (SEM) for the NSAA\u003csup\u003e9\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;In supportive analyses (see Table 5), paired equivalence testing showed that Telehealth and Asynchronous scores fell within SEM-based equivalence margins (equivalence p \u0026lt; 0.001 for all comparisons). These findings support clinical comparability between administration methods while acknowledging a small systematic difference that was not clinically meaningful.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eScores were also highly similar between the \u003cstrong\u003escoring methods\u003c/strong\u003e of the Telehealth administration of the NSAA, with live scoring (26.1 [5.67]) resulting in a 0.6 point (2.3%) higher score on average than scoring of the recorded Telehealth session (25.5 [5.54]). In supportive paired analyses, Live and Recorded Telehealth scores were observed to fall within both MCID- and SEM-based equivalence margins, supporting the robustness of Telehealth scoring regardless of whether assessments were scored in real-time or from recorded sessions.\u003c/p\u003e\n\u003cp\u003eMean NSAA scores were similar across the three assessment \u003cstrong\u003ewindows,\u0026nbsp;\u003c/strong\u003eBaseline, 3-Month, and 6-Month. The mean NSAA score at Baseline and 3-Month was identical (25.4 , with a negligible increase at Month 6 (25.5). These values represent combined Asynchronous and Telehealth assessment scores, with no clinically meaningful differences observed across assessment windows.\u003c/p\u003e\n\u003cp\u003eThe NSAA scores were consistent between raters within each NSAA scoring assignment, regardless of the \u003cstrong\u003escoring method\u003c/strong\u003e. The mean absolute difference (and standard deviation) between the two rater scores across all scoring methods was 1.87 (1.52). Inter-rater agreement was high across all scoring methods. The mean absolute difference between paired rater scores for all NSAA assessments was 1.87 (1.52) points. Inter-rater differences were slightly greater for Asynchronous assessments (2.15 [1.75] points) compared with Telehealth assessments (1.61 [1.22] points).All observed rater differences remained below established MCID and SEM thresholds, indicating acceptable agreement regardless of administration modality.\u003c/p\u003e\n\u003ch2\u003eSecondary Outcomes:\u003c/h2\u003e\n\u003ch3\u003e1.\u0026nbsp;\u0026nbsp;Rater Experience \u0026nbsp;\u003c/h3\u003e\n\u003cp\u003eOverall, the 6 raters (see \u003cem\u003eFigure 2)\u0026nbsp;\u003c/em\u003edemonstrated increased confidence in their personal ability to administer and score the NSAA using telehealth and video technology over the approximate 15-month period between the pre- and post-surveys. Their perceptions of telehealth as a viable tool for outcomes assessments as well as their belief in the feasibility of completing the NSAA effectively via telehealth also improved during this time. Additionally, raters reported greater comfort with administering the NSAA via telehealth in the post survey compared to pre-survey. Please see \u003cem\u003eTable 6\u003c/em\u003e for final rater demographics.\u003c/p\u003e\n\u003ch3\u003e2.\u0026nbsp;\u0026nbsp;Caregiver Experience\u003c/h3\u003e\n\u003cp\u003eAt the conclusion of the study, a majority of caregivers preferred in-person or indicated no preference, when asked whether they had a preference for administrative methods to capture the NSAA (specifically: \u0026ldquo;\u003cem\u003eAs the caregiver, how would you prefer to participate in routine mobility or activity assessments like the NSAA (e.g., walking or steps) conducted by a Physical Therapist?\u003c/em\u003e\u0026rdquo;). Overall, there was only a modest change from pre- to post study preferences. Please see \u003cem\u003eTable 7\u003c/em\u003e for the caregiver-preferred setting of assessment breakdown and \u003cem\u003eTable 8\u003c/em\u003e for reasons expressed when in-person at clinic was preferred. Given perceived burdens for In Person visits, we also consider this counter-intuitive data further in the Discussion section.\u0026nbsp;\u003c/p\u003e\n\u003ch3\u003e3.\u0026nbsp;\u0026nbsp;Training Material Feedback from Caregivers\u003c/h3\u003e\n\u003cp\u003eOverall, a large majority of caregivers found the training materials and instructions to be helpful and easy to understand for remote NSAA administration using telehealth and video technology.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWhen considering the training videos viewed within the mobile application, 88% of caregivers found the videos to be easy to understand and helpful with guiding the performance of the NSAA activities. Additionally, 94% of caregivers did not think there were areas where the training videos could be improved. When considering the caregiver manual, 94% of caregivers found the manual easy to understand while 100% found it helpful in guiding the performance of the NSAA activities.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAlthough the positive response rate fell just short of 100%, the difference was accounted for entirely by neutral responses; importantly, no respondents indicated that the materials were difficult to understand or unhelpful.\u003c/p\u003e\n\u003ch3\u003e4. \u0026nbsp;Data Availability\u003c/h3\u003e\n\u003cp\u003eThe datasets generated and/or analyzed during the current study are anonymized but not publicly available due to privacy and ethical considerations, including the potential risk of de-identification. Data are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eIn the context of rare disease research, the number of treated patients is typically small. This constraint raises the critical importance of long term follow up, post-approval confirmatory studies, outcomes registries, and generating data across the disease population and individual patients. For affected patients and their families, tracking outcomes and longitudinal changes is essential for understanding disease progression relative to natural history. While this need is recognized, it presents ongoing challenges and burdens for clinicians and patients alike. Consequently, the identification, evaluation and validation of innovative clinical follow up methodologies are imperative to ensure the collection of key follow up measures while minimizing the burden for families.\u003c/p\u003e \u003cp\u003eThis study contributes to the growing body of literature on remote administration of neuromuscular clinical outcomes assessments by validating and extending insights into the performance of the NSAA in home settings. The effectiveness of training materials, the feasibility of PT-led telehealth and caregiver-led at-home collection, and the consistent and reliable scoring of outcomes collectively demonstrate that NSAA remote administration is feasible and reliable.\u003c/p\u003e \u003cp\u003eThese findings have important implications for expanding access, reducing travel burden, and increasing flexibility for families engaged in ongoing clinical monitoring. Nonetheless, it is essential to acknowledge that caregiver and principal investigator (PI) preferences may vary, and some families may benefit from or prefer in-clinic assessments. Therefore, future post-approval implementation strategies should, where possible, consider designing with flexibility in mind, allowing for both remote and in-person options tailored to individual family circumstances, technological capabilities, and clinical requirements.\u003c/p\u003e \u003cp\u003eThe most notable finding of this study is the demonstrated accuracy, consistency, and reliability of the remote NSAA scoring. The involvement of multiple raters and assessment methods yielded results within the established margin of error for the NSAA. Based on these outcomes, we suggest that sponsors, regulators, payers, clinical personnel, and patients and their families can confidently consider remote administration and scoring provided that appropriate training, monitoring, and oversight mechanisms are put in place.\u003c/p\u003e \u003cp\u003eThe difference in mean scores between Asynchronous and Telehealth scoring methods (0.7 points), the difference between recorded and live Telehealth (0.6 points), and the mean difference between individual rater scores of all scoring methods (1.87 points) are all less than the NSAA\u0026rsquo;s published minimal clinically important difference of 2.3\u0026ndash;2.9 (or 6.5\u0026ndash;8.2 depending on the approach) or the standard error of measure of 2.9\u0026ndash;3.5.\u003c/p\u003e \u003cp\u003eThe mean difference between the two raters utilizing the Telehealth scoring method may have been smaller due to the ability to have the participant perform an item again or at a different angle to have a better look to better discern between item scores, where as the Asynchronous scoring method only provided the angles or attempts which the caregiver provided/captured, and the raters did not have a chance to improve a viewing angle to more accurately score. Regarding the finding that the live scoring resulted in a 0.6 point higher score on average when compared to the scoring of the recorded telehealth sessions, this difference may be due to the rater\u0026rsquo;s ability to watch the recording zoomed in and/or at different speeds and thus analyze movements patterns more specifically and accurately.\u003c/p\u003e \u003cp\u003eCaregiver responses to the training materials, along with the high compliance rate of submitted videos as reviewed by the study\u0026rsquo;s data management team further support the robustness of remote NSAA administration Notably, only 9/1071 (~\u0026thinsp;1%) of all study videos were missed/non-compliant with the NSAA protocol.\u003c/p\u003e \u003cp\u003eRegarding the raters\u0026rsquo; experience, the observed increased from pre- to post-study provides additional evidence in favor of adopting remote NSAA methodologies. Sponsors, PTs, and study personnel should prioritize comprehensive training and rigorous oversight to ensure the reliability and integrity of remote assessments.\u003c/p\u003e \u003cp\u003eAn unexpected finding in this study was the inconsistency between caregivers\u0026rsquo; stated preferences for assessment settings and their responses to the caregiver surveys. While a majority indicated a preference for telehealth or expressed no strong preference when asked directly, their survey responses revealed more nuanced attitudes, including concerns about technology reliability, comfort with remote interactions, and perceptions of accuracy of remote assessments. This discrepancy suggests that caregiver preferences may be context-dependent and influenced by factors such as prior experience, child-specific needs, and logistical considerations.\u003c/p\u003e \u003cp\u003eThis finding highlights the importance of offering flexible assessment options and engaging caregivers in an ongoing dialogue to ensure that chosen approaches align with evolving needs and expectations. While perhaps counter-intuitive of having the setting be performed consistently, the literature and this study\u0026rsquo;s data support the notion that the NSAA can be accurately scored in clinic and at home settings with accuracy. Being able to reference this study may help improve a caregiver\u0026rsquo;s confidence in the accuracy of remote assessments.\u003c/p\u003e \u003cp\u003eWe would also note that the Caregiver survey did not address the dimension of time. For example, preferences were not explored in the context of long-term clinical outcome extension study, such as those which required over a duration of a 5-to-10-year period in gene therapy or other rare disease follow-up scenarios. This temporal aspect may significantly influence caregiver preferences and warrants further investigation.\u003c/p\u003e \u003cp\u003eA limitation of this study is its exclusive use of remote administration methods, without a direct comparison to in-clinic assessments. Consequently, while the findings support the feasibility and acceptability of telehealth for administering the NSAA, they do not provide insight into how remote assessments may differ in accuracy, reliability, or caregiver/rater preference when compared to traditional in-person evaluations. However, Researchers are encouraged to refer to the work of Linda Lowes and colleagues, who conducted comparative studies addressing these dimensions.\u003c/p\u003e \u003cp\u003eFurther research incorporating a randomized or crossover design comparing remote and in-clinic NSAA administration would continue to add to the evidence and understanding on the relative.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eHuman Ethics and Consent to Participate:\u003c/h2\u003e\n\u003cp\u003eThis study was conducted in accordance with the principles of the Declaration of Helsinki. Approval was granted by WCG IRB (Study Number: 1358845) prior to initiating study activities. Written informed consent was obtained from both caregivers and participants prior to enrollment.\u003c/p\u003e\n\u003ch2\u003eCompeting Interests:\u003c/h2\u003e\n\u003cp\u003e\u0026nbsp;James D. Lastra, Julia Dailey Gothier, and Christopher Jones are employees of Red Nucleus, which owns the technology platform (iTakeControl) used in this study. These 3 authors are salaried employees and did not receive additional compensation related to this research. Red Nucleus received research funding from Pfizer, Inc. for the conduct of this study. Anna Stachel Kane and Nathaniel Posner are employees and shareholders of Pfizer, Inc. The remaining authors declare no conflicts of interest.\u003c/p\u003e\n\u003ch2\u003eFunding:\u003c/h2\u003e\n\u003cp\u003eThis study was funded by Pfizer, Inc. and conducted by Red Nucleus. Pfizer contributed to the study design but was not involved in study conduct or data analysis. Red Nucleus performed all data acquisition and analyses. Results were shared with Pfizer after analysis was completed.\u003c/p\u003e\n\u003ch2\u003eConsent for Publication:\u003c/h2\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003ch2\u003eAuthors’ Contributions:\u003c/h2\u003e\n\u003cp\u003eA.S.K, N.F., E.C.L., and C.J. wrote the main manuscript text. \u0026nbsp;A.S.K, N.F., E.C.L., J.D.L., N.P., and C.J. made substantial contributions to the design of the study and interpretation of the data. J.D.L \u0026nbsp; and J.D.G. \u0026nbsp;made substantial contributions to the acquisition and analysis of the data, wrote the main body of the results section, and created all tables and figures. All authors reviewed the manuscript and approved the submitted version. All authors have agreed to be both personally accountable for the author's own contributions and to ensure that questions related to the accuracy or integrity of any part of the work, even ones in which the author was not personally involved, are appropriately investigated, resolved, and the resolution documented in the literature.\u003c/p\u003e\n\u003ch2\u003eAcknowledgements:\u003c/h2\u003e\n\u003cp\u003eThe authors acknowledge Nic Valle, Katie Vetro, Amanda Long, Grace Kalala, and Jane Fiordeliso (Red Nucleus) for their contributions to the technology platform, study conduct, and data acquisition.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eNowak KJ, Davies KE. Duchenne muscular dystrophy and dystrophin: pathogenesis and opportunities for treatment. \u003cem\u003eEMBO Rep.\u0026nbsp;\u003c/em\u003e2004;5(9):872‑876. doi:10.1038/sj.embor.7400221\u003c/li\u003e\n \u003cli\u003eDuan D, Goemans N, Takeda S, Mercuri E, Aartsma-Rus A. Duchenne muscular dystrophy. \u003cem\u003eNat Rev Dis Primers.\u003c/em\u003e 2021;7(1):13. doi:10.1038/s41572-021-00248-3\u003c/li\u003e\n \u003cli\u003eKourakis S, Timpani CA, Campelj DG, Hafner P, Gueven N, Fischer D, Rybalka E. Standard of care versus new-wave corticosteroids in the treatment of Duchenne muscular dystrophy: can we do better? Orphanet J Rare Dis. 2021;16:117. doi:10.1186/s13023-021-01758-9\u003c/li\u003e\n \u003cli\u003eEmery N, Strachan K, Kulshrestha R, Kuiper JH, Willis T. Evaluating the feasibility and reliability of remotely delivering and scoring the North Star Ambulatory Assessment in ambulant patients with Duchenne Muscular Dystrophy. Children. 2022;9(5):728. doi:10.3390/children9050728\u003c/li\u003e\n \u003cli\u003eUS Food and Drug Administration. FDA grants accelerated approval to first drug for Duchenne muscular dystrophy. Silver Spring, MD: US Department of Health and Human Services, 19 September 2016. Available at: https://www.fda.gov/news-events/press-announcements/fda-grants-accelerated-approval-first-drug-duchenne-muscular-dystrophy. Accessed 28 February 2023.\u003c/li\u003e\n \u003cli\u003eAslesh T, Maruyama R, Yokota T. Skipping multiple exons to treat DMD\u0026mdash;promises and challenges. \u003cem\u003eBiomedicines.\u0026nbsp;\u003c/em\u003e2018;6(1):1. doi:10.3390/biomedicines6010001\u003c/li\u003e\n \u003cli\u003eWard SJ, Signorovitch J. Genetic Engineering \u0026amp; Biotechnology News. The problem with clinical trials in Duchenne\u0026mdash;and what we can do about it. 16 November 2021. Available at: https://www.genengnews.com/topics/genome-editing/gene-therapy/the-problem-with-clinical-trials-in-duchenne-and-what-we-can-do-about-it/. Accessed 28 February 2023.\u003c/li\u003e\n \u003cli\u003eMin YL, Bassel-Duby R, Olson EN. CRISPR correction of Duchenne muscular dystrophy. \u003cem\u003eAnn Rev Med.\u0026nbsp;\u003c/em\u003e2019;70:239‑255. doi:10.1146/annurev-med-081117-010451\u003c/li\u003e\n \u003cli\u003eScott E, Eagle M, Mayhew A, Freeman J, Main M, Sheehan J, Manzur A, Muntoni F. Development of a functional assessment scale for ambulatory boys with Duchenne Muscular Dystrophy. \u003cem\u003ePhysiother Res Int.\u0026nbsp;\u003c/em\u003e2012;17(2):101109. doi:10.1002/pri.520\u003c/li\u003e\n \u003cli\u003ehttps://www.physio-pedia.com/North_Star_Ambulatory_Assessment. Accessed 13 August 2025.\u003c/li\u003e\n \u003cli\u003eAyyar Gupta V, Pitchforth JM, Domingos J, Ridout D, Iodice M, Rye C, Chesshyre M, Wolfe A, Selby V, Mayhew A, Mazzone ES, Ricotti V, Hogrel JY, Niks EH, de Groot I, Servais L, Straub V, Mercuri E, Manzur AY, Muntoni F; iMDEX Consortium and the U.K. NorthStar Clinical Network. Determining minimal clinically important differences in the North Star Ambulatory Assessment (NSAA) for patients with Duchenne muscular dystrophy. PLoS One. 2023 Apr 26;18(4):e0283669. doi: 10.1371/journal.pone.0283669. PMID: 37099511; PMCID: PMC10132589.\u003c/li\u003e\n \u003cli\u003eSobierajska-Rek, A., Mański, Ł., Jabłońska-Brudło, J. \u003cem\u003eet al.\u003c/em\u003e Establishing a telerehabilitation program for patients with Duchenne muscular dystrophy in the COVID-19 pandemic. \u003cem\u003eWien Klin Wochenschr.\u0026nbsp;\u003c/em\u003e2021;133:344\u0026ndash;350. doi:10.1007/s00508-020-01786-8\u003c/li\u003e\n \u003cli\u003eTanner K, Bican R, Boster J, et al. Feasibility and acceptability of clinical pediatric telerehabilitation services. \u003cem\u003eInt J Telerehabil.\u003c/em\u003e 2020;12(2):43‑52. doi:10.5195/ijt.2020.6336\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1 to 8 are available in the supplementary files section\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-health-services-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bhsr","sideBox":"Learn more about [BMC Health Services Research](http://bmchealthservres.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/BHSR/default.aspx","title":"BMC Health Services Research","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-8980113/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8980113/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eRemote functional assessments can expand access and reduce burden for families affected by Duchenne muscular dystrophy (DMD), but evidence is needed on the reliability of remote administration and scoring of the North Star Ambulatory Assessment (NSAA). We conducted a non-interventional, mixed‑methods study using a 21 CFR Part 11–compliant video platform to compare NSAA scores from live telehealth versus caregiver‑captured asynchronous at‑home videos and to compare live versus recorded telehealth scoring (Clinical trial number: not applicable). Eighteen participants (mean age 8.7 years) completed NSAA at baseline, 3 months, and 6 months; assessments were double‑scored by NSAA‑certified physical therapists. Mean NSAA was 25.8 (telehealth) versus 25.1 (asynchronous); the 0.82‑point difference met two one‑sided tests for equivalence within ±3‑point SEM margins (p\u0026lt;0.001). Live versus recorded telehealth differed by 0.23 points and was also equivalent (p\u0026lt;0.001). Inter‑rater mean absolute difference was 1.87 points (telehealth 1.61; asynchronous 2.15), below the MCID threshold. Remote NSAA was feasible, reliable, and clinically comparable across methods, supporting decentralized follow‑up and data collection in DMD.\u003c/p\u003e","manuscriptTitle":"Use of Telehealth and At-Home Video for Remote Administration of the North Star Ambulatory Assessment (NSAA): A Comparative Methods Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-07 10:27:57","doi":"10.21203/rs.3.rs-8980113/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-04-26T16:53:03+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-19T21:07:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"294272505753719066255787240960405557619","date":"2026-04-14T16:28:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"226554184241504390613501958359943323598","date":"2026-04-09T17:13:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"27000448708747529492532147313980624252","date":"2026-04-08T18:52:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-01T15:29:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-31T06:21:47+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-06T05:17:11+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-05T21:27:36+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Health Services Research","date":"2026-03-05T15:00:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-health-services-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bhsr","sideBox":"Learn more about [BMC Health Services Research](http://bmchealthservres.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/BHSR/default.aspx","title":"BMC Health Services Research","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"af147a96-36a4-4ee9-97d8-d848b60ddf7c","owner":[],"postedDate":"April 7th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-04-07T10:27:58+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-07 10:27:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8980113","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8980113","identity":"rs-8980113","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}