ABSTRACT
Background and Aims
Accurate, reliable and sensitive clinical outcome measures in rare neurologic conditions, such as Charcot–Marie–Tooth disease (CMT), are essential for monitoring disease progression and evaluating treatment efficacy. Ensuring measures such as the CMTPedS, CMTInfS and CMT‐FOM are easily accessible removes a barrier to implementation. The aims of this project were to: (1) design a web‐based platform to enable real‐time scoring of CMT outcome measures; (2) implement co‐designed training and quality assurance resources; and (3) establish a Global Certification Standard for clinical evaluators.
Methods
A consultation process informed the design of the web‐based platform and included a process evaluation of current users (n = 65). Training resources were co‐designed with key stakeholders (n = 51) including CMT physicians and scientists, clinical evaluators, pharmaceutical representatives, and patients through a mixed‐methods approach. A Global Certification Standard was developed through the co‐design process and Master Trainer expertise.
Results
A web‐based platform, www.ClinicalOutcomeMeasures.org was designed and implemented in June 2020 as a freely available trial readiness resource for clinicians and researchers. The platform now has > 1400 registered users from > 45 countries. Clinical evaluators identified a lack of accessible training resources as the top barrier to accurate and reliable administration of CMT outcome measures. Video demonstrations, online workshops, and labelled photographs were ranked as the top training methods. Five guiding principles for the Global Certification Standard for CMT outcome measures were established.
Interpretation
The web‐based platform provides real‐time scoring of CMT outcome measures, access to standardized training, and a Global Certification Standard to support accurate and reliable assessment of disease severity, progression, and treatment efficacy.
Keywords: Charcot–Marie–tooth disease, clinical outcome measures, training and quality assurance, web‐based platform
1. Introduction
There are significant challenges to conducting clinical trials in rare neurologic diseases such as Charcot–Marie–Tooth disease (CMT). Over the past decade, accurate, reliable, and responsive clinical outcome measures for CMT have been developed and validated [1, 2, 3, 4, 5]. Clinical outcome measures are the core of clinical research in rare neurologic diseases. They provide objective, reproducible measures of functional health outcomes across the lifespan, from infancy through adulthood. Their validity and reliability are critical to ensuring that trial endpoints truly reflect patient benefit. These tools have enabled precise phenotypic characterization and provided meaningful endpoints for natural history studies and interventional trials. However, a significant challenge remains; eradicating inaccurate measurement of clinical outcome measures in clinical trials. The reliability of the data relies on robust quality and training frameworks for the clinical evaluators who administer the assessments [6]. The burden of inaccurate measurement is significant as it impacts results of trials and the ability to accurately assess the effect of novel therapeutics. Robust training and quality assurance systems are needed to ensure clinical evaluators from around the world are performing clinical outcome measures in the same reliable and precise way. Pharmaceutical trials have recognized the importance of data quality and mandate frameworks to ensure reliability between clinical evaluators and to avoid drift [7]. Training can improve the competency of clinical evaluators who have different levels of experience [8]. However, without a training and quality assurance framework, evaluator drift can occur over time, leading to inaccurate and unnecessary variability in the data.
CMT is the most common inherited peripheral neuropathy. The onset of the disease is frequently during childhood, causing progressive distal muscle weakness, sensory loss, painful foot deformities, impaired gait, and frequent falls [4]. There is currently no disease‐modifying treatment for individuals with CMT, but there is a promising pipeline of disease‐modifying therapies progressing from preclinical studies to human trials. Accurate, reliable, and sensitive clinical outcome measures exist across the lifespan in accordance with the four FDA categories, namely, Performance clinical outcome measures (CMT Pediatric Scale, CMTPedS [1]; CMT Infant Scale, CMTInfS [3]; CMT Functional Outcome Measure, CMT‐FOM [2] scored using the world's most comprehensive set of normative reference data for measures of physical function across the lifespan, the 1000 Norms Project [9, 10, 11, 12]), Patient‐reported clinical outcome measures (Pediatric CMT Quality of Life Outcome Measure 8–18 years [13]), Observer‐reported clinical outcome measures (Pediatric CMT Quality of Life Outcome Measure Parent Proxy 0–7 [14] and 8–18 years [15]), and Clinician‐reported clinical outcome measures (Rasch‐modified CMT Neuropathy Score and Exam Score [16]).
These clinical outcome measures reflect outcomes that are meaningful to patients, ensuring the ability to evaluate treatment efficacy and the magnitude of difference made to functional problems children and adults with CMT face. To support global implementation of these clinical outcome measures, a robust quality assurance and training framework [7, 17, 18] is needed along with a Global Certification Standard that ensures clinical evaluators are qualified, trained, and consistently applying standardized procedures [19].
Inaccurate measurement causes unnecessary delays in the translation of new therapies for people with rare neurologic diseases, such as CMT. It is necessary that sites globally are trial ready. Therefore, the aims of this project were to: (1) design a web‐based platform to enable real‐time scoring of CMT clinical outcome measures based on the 1000 Norms Project dataset; (2) implement co‐designed training and quality assurance resources; and (3) establish a Global Certification Standard for clinical evaluators to promote accurate and reliable data collection.
2. Materials and Methods
2.1. Web‐Based Scoring Platform
A comprehensive consultation process including user interviews (n = 5) and co‐design workshops (n = 3) with the development team informed and guided the development of the freely available web‐based platform, www.ClinicalOutcomeMeasures.org. The digital platform's implementation involved a process evaluation of current users (n = 65 clinical evaluators from the USA, Australia, Italy, UK, Columbia, Germany, Netherlands, Brazil, Canada, Chile, India, Sweden, Switzerland), and the establishment of key design elements including user experience, technical requirements, and embedded Google Analytics. A website designer, Webqem (webqem Pty Ltd., Sydney, Australia) created an online portal hosting learning materials, resources, and clinical outcome measure calculators. Extensive calculator testing by CMT Master Trainers (KMDC, MJM) was conducted to verify the accuracy of the translation of these calculators to the digital platform. Google Analytics and a registration process were employed to monitor portal users.
2.2. Training Resources
eHealth training resources were co‐designed through a collaborative, multi‐method approach. To inform the development of user‐friendly, informative training resources for clinical outcomes, a survey was conducted with 21 clinical evaluators from the Inherited Neuropathy Consortium (INC #U54NS065712, PI Michael Shy). The survey assessed baseline awareness, current use, level of training in clinical outcome measures, as well as preferred content and format of training resources. Other key stakeholders (community clinicians interested in using the CMT or the 1000 Norms Project clinical outcome measures, n = 5; pharmaceutical representatives who may use these measures in clinical trials, n = 2; and patient advocacy group representatives, n = 3) of the clinical outcome measures were invited to participate in interviews to discuss how to address their training needs for the clinical outcome measures. Results from the survey responses and interviews were used to ensure the training resources were designed to meet the needs of all key stakeholders and guide the successful implementation of these measures into research studies, clinical trials, and clinical practice. Institutional Review Board approval was attained from Sydney Children's Hospitals Network Human Research Ethics Committee (2021/ETH01139) and informed consent was obtained from all clinical evaluators and participants and/or their parents/guardians for the video capture.
2.3. Global Certification Standard
Online tutorials and guides to introduce the basic principles of clinical outcome measures were developed by expert clinician‐researchers (JB, KMDC). Professional videos and still images of each item of the CMTPedS, CMTInfS, and CMT‐FOM and the 1000 Norms Project assessments were captured. Twenty consenting male (n = 9) and female (n = 11) pediatric and adult participants were recruited for these videos. Videos included pediatric (n = 9) and adult (n = 11) participants (9 patients with CMT1A, 1 patient with CMT1F and 10 healthy controls). A total of 215 videos and still images were captured, edited, and formatted by a professional videographer (Cahoots, Sydney Australia) to ensure high‐quality training resources were produced. Videos were reviewed by expert clinical evaluators (JB, KMDC, MJM). The e‐training and quality assurance platform was developed using Kando Central Learning Management System (Interaction Training Pty Ltd., Sydney, Australia) in collaboration with web developers from Webqem and linked to http://www.clinicaloutcomemeasures.org. Institutional Review Board approval was attained from Sydney Children's Hospitals Network Human Research Ethics Committee (2021/ETH01139) and St Jude Children's Research Hospital (CERTIFYCMT, 25–1935).
To support the global implementation of these clinical outcome measures, a robust quality assurance and training framework has been established by the CERTIFYCMT steering committee comprising 8 expert CMT clinicians and researchers. The quality assurance and training framework includes a Global Certification Standard that ensures clinical evaluators are qualified, trained, and consistently applying standardized procedures, particularly for any upcoming clinical trials.
3. Results
3.1. Web‐Based Scoring Platform
The web‐based platform www.ClinicalOutcomeMeasures.org was developed as a freely available resource providing clinicians worldwide access to online, real‐time scoring calculators for the CMT clinical outcome measures (Figure 1). The platform is designed to support future expansion across other rare diseases. The first expansion was to include a clinical outcome measure for Riboflavin Transporter Deficiency [20]. Riboflavin transporter deficiency, caused by biallelic pathogenic variants in SLC52A2 and SLC52A3, is a rare progressive peripheral and cranial neuronopathy characterized by sensory ataxia, muscle weakness, vision loss, bulbar palsy, respiratory compromise, and deafness [21].
FIGURE 1.
Home page of www.ClinicalOutcomeMeasures.org.
Access to the platform requires free registration. Users can initiate this by clicking “Log in” at the top right corner of the homepage and completing the registration form. New registrations are monitored and approved. If additional information is required, users will receive a follow‐up email. Equipment and Training Resource Manuals are available for download on www.ClinicalOutcomeMeasures.org with links to all scientific publications and language translations. Bulk upload scoring is available by request for batch processing of multiple assessments at once with processing of > 1000 individuals occurring in < 1 minute. The calculators and bulk upload processing instantly score clinical outcome measures and provide downloadable reports of these scores in excel format. No data are stored on the website to ensure data security and privacy.
There are > 1400 registered users on www.ClinicalOutcomeMeasures.org from > 45 countries with new registrations every week. http://www.clinicaloutcomemeasures.org is being used in ongoing natural history studies and clinical trials (NCT01193075, NCT03550300, NCT03888716, NCT05011006, NCT05600764, NCT05397665, NCT06151600, NCT06482437).
3.2. Training Resources
Twenty‐one international clinical evaluators completed the online survey (Table 1). Respondents identified the lack of accessible training resources as one of the top three barriers to reliable/precise clinical outcome measure use (Figure 2). Video demonstrations, online workshops, and labelled photographs were ranked as the top 3 training methods (Table 2). Clinical evaluators identified areas requiring further training (Table 3) and preferred methods for initial and refresher training (Figure 3). Interviews with CMT experts, pharmaceutical representatives, and patients identified the need for comprehensive training resources, including how to perform assessments as well as common compensations to watch for in participants and common errors by clinical evaluators. It was suggested to use a range of training resources, including written materials, photographs, and videos.
TABLE 1.
Clinical evaluator demographics.
| Characteristic | Frequency (%) |
|---|---|
| Sex | Females: 14 (67%) |
| Males: 7 (33%) | |
| Age | 20–30 years: 2 (9.5%) |
| 31–40 years: 3 (14%) | |
| 41–50 years: 10 (48%) | |
| 51–60 years: 4 (19%) | |
| 61 + years: 2 (9.5%) | |
| Location | USA: 11 (53%) |
| UK: 3 (14%) | |
| Italy: 4 (19%) | |
| Australia: 3 (14%) | |
| Highest level of academic achievement | Doctorate (MD, PhD or DPT): 10 (48%) |
| Masters: 4 (19%) | |
| Bachelors: 5 (24%) | |
| Post‐graduate certificate/diploma: 2 (9%) | |
| Clinical Degree | Physiotherapy: 6 (29%) |
| Occupational Therapy: 3 (14%) | |
| Medical (Neurologist, Pediatrician): 8 (38%) | |
| Other (exercise physiologist, biomed engineer, dietician, research assistant): 4 (19%) | |
| Number of years working as a clinical evaluator with patients with CMT | < 2 years: 3 (14%) |
| 2–5 years: 2 (10%) | |
| 6–10 years: 5 (24%) | |
| > 10 years: 11 (52%) | |
| Experience assessing patients age groups with CMT | Pediatric: 8 (38%) |
| Adult: 6 (29%) | |
| Both Pediatric and Adult: 7 (33%) | |
| Training in CMT outcome measures | CMTInfS: 7 (33%) |
| CMTPedS: 15 (71%) | |
| CMT‐FOM: 10 (48%) | |
| No training: 3 (14%) |
FIGURE 2.
Barriers to reliable and precise clinical outcome assessments.
TABLE 2.
Preferred training method ranked by 21 clinical evaluators.
| Training method | Mean ranking |
|---|---|
| Video demonstrations | 3.6 |
| Online/tele‐conference workshops | 3.9 |
| Labelled photographs | 4.3 |
| Recorded expert tutorials | 4.3 |
| Printed manuals | 4.3 |
| In‐person workshops | 4.6 |
| Power Point presentations | 4.9 |
| Online quizzes with feedback | 5.1 |
Note: Training methods were ranked from 1 (Most preferred) to 8 (least preferred).
TABLE 3.
Areas identified by clinical evaluators requiring further training.
| Area | Percentage of clinical evaluators (n = 21) |
|---|---|
| Patient positioning during assessments | 38.1 |
| Reporting results of outcome measures | 33.3 |
| Interpretation of scores | 28.6 |
| Scoring of items | 19.1 |
| Calibrating/setting up necessary equipment | 19.1 |
| Calculating z‐scores | 14.3 |
| Use of online calculators | 14.3 |
| Preparing the environment for assessments | 9.5 |
| Selecting the appropriate equipment needed | 9.5 |
FIGURE 3.
Preferred method of training for a new clinical outcome measure.
3.3. Global Certification Standard
The videos captured feature patients with a range of disease severity (mild, moderate and severe on the clinical outcome measures). Professional images were used to update comprehensive equipment and training resource manuals for each of the performance clinical outcome measures. Online tutorials, guides, and professional videos of the correct assessment procedures for performance clinical outcome measures were used to develop online basic training courses for each scale. The basic training courses include quizzes to test comprehension of clinical evaluators. Professional videos of common compensations to watch for in participants and common errors by clinical evaluators were used to develop advanced training courses for each scale where clinical evaluators need to be able to identify the compensation or error made, with examples of correct/incorrect techniques.
The training and quality assurance resources, including manuals and basic and advanced courses, were developed into online learning programs using Kando Central Learning Management System (Figure 4). Registration is required via the training tab on www.ClinicalOutcomeMeasures.org. Once registration is approved, you will get an e‐mail notification. The online learning programs include sequential basic and advanced level courses for the CMTPedS, CMTInfS, and CMT‐FOM. Each learning program provides certificates of completion.
FIGURE 4.
Clinical evaluator training and quality assurance program. Available at www.ClinicalOutcomeMeasures.interactiontraining.net, but registration is required on www.ClinicalOutcomeMeasures.org.
Following a series of reviews, consensus was reached among the expert CMT clinicians and researchers for a Global Certification Standard based on five key guiding principles shown in Figure 5 including: (1) Qualified clinical evaluators (2) Certification and ongoing training (3) Site readiness (4) Standardized administration and (5) Consistent scoring.
FIGURE 5.
Principles for the Global Certification Standard.
4. Discussion
The web‐based platform, http://www.clinicaloutcomemeasures.org provides freely available real‐time scoring of CMT outcome measures, access to standardized training, and a Global Certification Standard to support accurate and reliable assessment of disease severity, progression, and treatment efficacy. The clinical outcome measures available on this website can be more broadly implemented into clinical practice, research studies, and clinical trials. By providing accessible, standardized tools and training, the web‐based platform supports consistent and reliable measurement and scoring of disease severity, progression, and treatment efficacy across diverse settings. This enables greater participation in multisite research and enhances the quality of data collected across clinical and research environments. Furthermore, continued access to training resources will allow for ongoing maintenance of training to improve reliability in assessments over time. The Global Certification Standard outlines five principles for high‐quality clinical evaluations in CMT.
By co‐designing the web‐based platform, a user‐friendly online scoring website and resource hub was developed that is extensively used by researchers and clinicians worldwide. The comprehensive, informative training resources for clinical outcome measures address the need for robust training and quality assurance systems to ensure that clinical evaluators globally are performing clinical outcome measures in the same reliable and precise way. Availability of the training and quality assurance program will help ensure data quality and accuracy of assessments. It has been previously shown that training on a single occasion can result in poor reliability [22], while continual access to training resources on the web‐based platform may overcome this barrier. It has been previously highlighted that ongoing training, regardless of clinical experience, is essential [23].
The five key guiding principles of the Global Certification Standard are essential to generating high‐quality data for clinical trials that can inform regulatory decisions. Ensuring clinical outcome measures are administered by healthcare professionals who are thoroughly trained and certified as clinical evaluators and have general expertise in the assessment of infants, children, and/or adults is essential to generating accurate and reliable endpoints. This is particularly important in pediatric patients where difficulties with cooperation at young ages can occur. Clinical evaluator qualification, experience, and training are essential to overcome these challenges and ensure accurate and reliable assessments.
This project is not without limitations, including that the clinical evaluator training and quality assurance program is currently limited to English. Both the web‐based calculator platform and online training course require internet connectivity, which may pose challenges in developing countries. In the future, we plan to continue to expand our video resource library to support annual refresher training and increase accessibility through diverse, multilingual content that reflects the global population these clinical outcome measures are intended for. We also plan to compare the effectiveness of online training to the traditional in‐person process for clinical outcome measure training. Further developments will incorporate artificial intelligence to further enhance training and clinical trial readiness, including automated scoring validation using AI‐assisted video analysis to support evaluator accuracy and consistency and predictive analytics to identify gaps in clinical evaluator performance or site readiness across global networks.
In conclusion, the web‐based platform, www.ClinicalOutcomeMeasures.org, allows implementation of the CMT clinical outcome measures based on the 1000 Norms Project into global clinical and research environments to enable real‐time scoring and reporting. The platform has the ability to continue to expand and include other outcome measures used in other diseases. A collaborative approach was used to design and develop user‐friendly training resources meeting the needs of clinical evaluators. A digitally enabled infrastructure was established to support a clinical evaluator training and quality assurance program. Accurate measurements will allow for rapid translation of effective therapeutic studies to clinically approved therapies for patients with CMT.
Conflicts of Interest
The authors declare no conflicts of interest.
Acknowledgements
The authors acknowledge funding for this project from the Muscular Dystrophy Association (MDA Ideas Grant: 876246 and MDA Research Infrastructure Grant: 1060929, https://doi.org/10.55762/MDA.1060929.pc.gr.195081) and the Inherited Neuropathy Consortium (Inherited Neuropathy Consortium Pilot Grant). The authors acknowledge the participants involved in video capture for creating the online training resources, the Inherited Neuropathy Consortium investigators for their work developing the clinical outcome measures included in this web‐based platform, and the CERTIFYCMT Study Group for their contributions to developing the Global Certification Standard.
Cornett K. M. D., Estilow T., Bray P., et al., “Designing and Implementing a Web‐Based Platform for Accurate and Reliable Clinical Outcome Measures and Global Certification for Evaluating Charcot–Marie–Tooth disease,” Journal of the Peripheral Nervous System 30, no. 3 (2025): e70062, 10.1111/jns.70062.
Funding: This work was supported by Muscular Dystrophy Association, 876246, 1060929. Inherited Neuropathy Consortium.
Marnee J. McKay and Joshua Burns are joint senior authors who contributed equally.
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.