Autism spectrum disorder (ASD) is a lifelong neurodevelopmental condition characterized by persistent differences in social communication and interaction, alongside restricted and repetitive patterns of behavior and interests [1]. Beyond these core diagnostic features, many autistic individuals experience clinically meaningful motor impairments, including reduced coordination, poor balance, atypical gait, and diminished muscle strength [2-5]. These impairments often persist into adulthood and across the life course [6-9], yet they remain relatively underrecognized in adult ASD research and clinical care. Motor limitations may reduce participation in physical activity (PA), increase sedentary behavior, and contribute to an elevated risk of falls, obesity, and chronic health conditions, ultimately affecting overall functioning and quality of life (QoL).

Despite their relevance, motor impairments and physical function remain underresearched in adults with ASD. These domains are not included in diagnostic criteria, are inconsistently assessed in clinical practice, and are infrequently addressed through movement-based rehabilitation strategies [2,10,11]. The limited use of standardized, objective measures of physical function in autistic adults also restricts the ability to evaluate intervention effects, monitor change over time, and tailor supports to individual needs [10]. This gap underscores a pressing need for accessible, valid, and reliable methods to assess physical function and motor performance in adults with ASD.

Barriers to health care access further complicate the evaluation and management of physical function in this population. Adults with ASD often encounter communication challenges, sensory sensitivities, anxiety, and limited provider familiarity with adult ASD, all of which may interfere with effective assessment and treatment [12-14]. These barriers are often compounded for racial and ethnic minority populations, who may also experience delayed diagnosis, underrecognition of co-occurring conditions, and structural inequities in care [15-17]. Additional barriers related to transportation, geography, financial constraints, and health system complexity may further reduce participation in clinic-based care [18-20]. Telehealth-based approaches may help address these barriers by reducing logistical burdens, minimizing sensory and social stressors, and expanding participation in both research and clinical services.

Telehealth has emerged as a practical modality for functional assessment in both clinical and research settings. Synchronous telehealth allows for real-time administration and observation of performance-based measures, whereas asynchronous video review allows repeated observation, more detailed scoring, and evaluation of interrater and intrarater reliability [21-24].

Together, these approaches may improve accessibility while preserving observational rigor. However, although telehealth-based rehabilitation and remote monitoring are increasingly used, standardized evaluations of physical function in adults with ASD remain limited, and psychometrically supported remote assessment methods for this population are largely absent from the literature [2,10,11].

This protocol addresses this gap by examining the feasibility, construct validity, and rating reliability of remotely administered physical function assessments in adults with ASD. Consistent with the analytic plan, the study evaluates the construct validity of patient-reported physical function using related indicators of health and functioning, including PA, lower-extremity function, fall risk, and comorbidity burden, while also examining remote performance-based measures as exploratory complementary indicators of physical function. The protocol additionally investigates racial and ethnic disparities in physical function, PA, fall risk, and QoL and evaluates whether the relationships among physical function, PA, and QoL differ by race and ethnicity. By focusing on telehealth-delivered assessments and equitable inclusion of racial and ethnic minority participants, this study seeks to inform more accessible and inclusive approaches to physical function assessment in adults with ASD.

This study is guided by the Model of Healthcare Disparities and Disability (MHDD) [25], which extends disability-focused frameworks by explicitly incorporating health care access, system-level barriers, and contextual influences on functioning and health outcomes.

Whereas the International Classification of Functioning, Disability, and Health (ICF) [26] recognizes the interaction among body functions, activity, participation, and contextual factors, the MHDD more directly emphasizes how mismatches between individual characteristics and environmental or health system conditions can contribute to reduced access to care, diminished functioning, and poorer health outcomes among people with disabilities (see Figure 1) [25]. Within this framework, remotely administered physical function assessment is conceptualized as a strategy to reduce environmental and health care access barriers that may disproportionately affect adults with ASD, particularly those from underserved or racial and ethnic minoritized groups. Telehealth may support participation by allowing assessment to occur in a familiar environment and by reducing transportation-related burden, clinic-related stress, and sensory overload. In this way, remote physical function assessment is positioned not only as a methodological innovation but also as a potential mechanism for improving access to health services relevant to physical functioning.

Although QoL is not represented as a discrete construct within the MHDD, it is closely related to the model’s emphasis on functioning, participation, and contextual fit of the individual. Inadequate access to appropriate health services, environmental barriers, and poor alignment between individual needs and care delivery may negatively influence functioning and participation, thereby affecting QoL. In this protocol, QoL is conceptualized as an important downstream outcome linked to physical function, PA, health burden, and access-related factors. The MHDD provides a useful framework for understanding how remotely delivered physical function assessments may support more equitable health evaluations and, ultimately, more responsive care for adults with ASD.

This paper presents the protocol for a pilot study designed to evaluate the feasibility, construct validity, and rating reliability of remotely administered physical function assessments in adults with ASD, with attention to racial and ethnic equity in participation and outcomes.

This study has three primary aims:

This protocol is intended to provide foundational evidence for more accessible, equitable, and scalable approaches to physical function assessment in adults with ASD. If the planned hypotheses are supported, the findings may inform future larger-scale studies and telehealth-based rehabilitation strategies aimed at improving physical function, PA, and QoL in this population.

This pilot study will use a 2-phase, cross-sectional, noninterventional design with remote data collection in adults with ASD, with targeted recruitment of individuals from underrepresented racial and ethnic groups. This study uses a nested design. The full sample of participants will complete the self-report and wearable activity monitoring components of the study. Within this overall sample, a randomized subset of 25 participants will also complete Phase 1, which consists of a remote telehealth-based performance assessment session. Accordingly, Phase 1 participants are included within the overall study cohort and are not treated as a separate sample.

This study was approved by the Institutional Review Board of Florida International University (Protocol #IRB-24-0230-AM5; TOPAZ Reference #113500). Electronic informed consent will be obtained from all participants prior to study participation. Participant data will be deidentified and handled in accordance with institutional and applicable regulatory requirements for privacy and confidentiality. Data were securely stored and managed using REDCap (Vanderbilt University).

Eligible participants will be adults with a self-reported professional diagnosis of ASD registered in the Simons Powering Autism Research and Knowledge (SPARK) registry. SPARK is a nationwide database of individuals residing in the United States and will serve as the recruitment source for this study [27]. The registry has demonstrated high diagnostic validity (98.8% agreement rate) [28] and includes over 13,000 adults, approximately 55% of whom are legally independent. Participants will be required to have access to a personal computing device with internet connectivity and the ability to complete remote assessments.

The inclusion criteria are legally independent adults with ASD aged 18-59 years, with a previous professional diagnosis or educational classification of ASD, autism/autistic disorder, Asperger syndrome, or pervasive developmental disorder not otherwise specified. Participants will be registered with the SPARK network, and their available registry data must include age at registration, sex, race, ethnicity, professional or professionals who provided the ASD diagnosis, age at initial diagnosis, lifetime receipt of services, participation in an individualized education program or other ASD-specific programs, and autism severity as measured by the Social Responsiveness Scale (SRS). Persons will be excluded from the study if they have any open wounds, fractures, severe visual or hearing impairments, or health conditions that prevent them from standing up from a chair or standing on either leg or that preclude safe participation in remote assessment.

To target the recruitment of adults with ASD from underrepresented racial and ethnic groups, we will implement a multipronged strategy in collaboration with the SPARK Research Match service. Research Match, an integrated service of the Simons Foundation Autism Research Initiative (SFARI), enables approved investigators to recontact SPARK participants for new studies. The platform supports both remote and in-person research and streamlines enrollment by integrating invitation, eligibility screening, and survey access into a single system. Recruitment will be conducted via email outreach through SPARK’s “batched recruitment” infrastructure, which allows invitations to be distributed in waves to selected subsets of eligible participants until the enrollment targets are met. Stratified sampling will be used to ensure the representation of Black/African American and Hispanic/Latino participants, with random selection continuing until quotas of 50 participants per group are achieved.

Eligible individuals will be invited to review and electronically sign informed consent forms. We plan to enroll a total of 155 participants. All enrolled participants will complete the self-report and wearable activity monitoring components of the study. Within this overall sample, a randomized subset of 25 participants will be invited to complete the Phase 1 remote telehealth-based performance assessment session. Thus, the Phase 1 subset is nested within the full study sample.

The study includes three main forms of data collection: (1) telehealth-delivered performance-based physical function assessments, (2) self-report survey measures, and (3) wearable activity monitoring of daily step counts. Measures were selected following a review of available assessments with an emphasis on usability, accessibility, and relevance for adults with ASD, including consideration of the sensory, cognitive, and motor features that may influence remote assessment participation and performance. A summary of health outcome measures and related International Classification of Functioning, Disability and Health domains is provided in Table 1, and the sequence of outcome measure assessments is provided in Figure 2.

Study activities are organized into 2 linked phases within a nested design. Phase 1 focuses on the remote telehealth-based performance assessment component and is completed by a randomized subset of 25 participants drawn from the overall study cohort. Phase 2 includes the full study sample and comprises self-report survey measures and wearable activity monitoring. Thus, all enrolled participants complete the Phase 2 components, whereas the Phase 1 subset additionally completes the remote performance-based assessment protocol.

All participants will complete online survey measures using REDCap and will be mailed a Fitbit Inspire 3 (Google LLC) device to wear for 2 weeks. Daily step-count data will be downloaded through the Fitabase (Small Steps Labs, LLC) platform. Completion of self-report surveys and wearable-monitor compliance for 2 weeks is required for participation in the full study sample. For the nested Phase 1 subset, participation also includes one 60-minute telehealth-based physical function assessment session.

In Phase 1, a randomized selection of 25 participants will undergo remote telehealth-based physical function assessments via secure platforms using their personal computing devices. The telehealth assessment includes a complete battery of physical function, including the Five Times Sit-to-Stand (5xSTS), 30-second Sit-to-Stand (30sSTS), standing balance (eyes open [EO] and eyes closed [EC]), and Single-Leg Stance (SLS; EO and EC). All assessments will be recorded to support intra- and interrater reliability analyses across 6 independent raters. Feasibility will be evaluated based on completion rates, participant feedback, and technical challenges.

To assess interrater reliability of video-recorded remote assessments, the primary rater, a licensed physical therapist (PT) with expertise in functional outcome measures and experience working with individuals with ASD, will train 4 second-year and 3 third-year Doctor of Physical Therapy (DPT) students from the same academic institution. Training will include structured instruction on scoring procedures, video-based calibration sessions, and a formal agreement check-off to ensure consistency prior to data collection. All raters will also receive specialized training in safety monitoring tailored to the ASD population.

Calibration will be conducted using 3 mock video-recorded assessments representing the study performance battery. To qualify for independent scoring, each student rater must achieve at least 80% agreement with the primary rater across scored items during the formal check-off. Raters who do not meet this criterion will receive additional feedback and retraining and will repeat calibration until the required agreement level is achieved before scoring study recordings independently.

Although licensed PTs typically administer remote functional assessments, supervised DPT students may contribute as part of their clinical training. Their involvement in this study highlights the potential for integrating student participation into telehealth-based evaluations and may support broader implementation in educational and clinical settings.

Prior to the scheduled session, participants will receive an email with detailed instructions to prepare their environment and equipment. Participants will also be encouraged to log into Zoom (Zoom Video Communications, Inc) a few minutes early to troubleshoot any technical issues. Additionally, given the unique sensory, cognitive, and motor coordination profiles of adults with ASD, additional safety measures will be implemented, and the email will include the following guidance and recommendations when possible:

Given the unique sensory, cognitive, and motor coordination profiles of adults with ASD, additional safety measures will be implemented. Once the participant and rater have successfully logged into the secure Zoom video platform, the rater will greet the participant; confirm readiness; and identify any sensory sensitivities, communication preferences, or physical limitations that may affect test performance. All raters will ensure the following safety measures and instructions are provided to the study participant to optimize remote testing sessions: (1) new or recent medical conditions, injuries or changes in physical status that may affect test performance; (2) quiet environment, when possible, the study participant will be encouraged to choose a space that is quiet and free from distractions to help with focus during the evaluation; and (3) computer setup, participants will be encouraged to position a computer or device so that the rater can see their entire body during the tests. The camera should also be at a height that allows the rater to see them sitting and standing. If necessary, the rater will use their own device to demonstrate body positioning and spacing expected of the participant. Testing sessions will be paused or discontinued if participants exhibit safety concerns, including but not limited to dizziness, chest pain, shortness of breath, loss of balance, or expressed discomfort. The trained assessor conducting the session will make the determination to pause or terminate testing based on these criteria.

Each participant will complete a remote telehealth-based performance assessment session, which will be video-recorded. Following the safety check, the rater may begin the remote-based performance assessment. The evaluation will include standardized performance-based functional assessments, including the 5xSTS test, 30sSTS, modified Berg Balance Scale (BBS) items (standing EC/EO), and SLS test. These assessments will be conducted in real time by a trained rater and are designed to measure lower extremity strength, balance, and functional mobility. The rater will provide the following to optimize testing procedures. First, clear instructions and demonstrations to all study participants will be given. All test procedures will be explained using simple, direct language. Visual demonstrations will be provided, and participants will be allowed to practice each movement before formal testing begins. Second, real-time monitoring will be used, ensuring that the rater continuously monitors participant posture, movement quality, and signs of distress or fatigue. Testing will be paused or discontinued if safety concerns arise. Third, rest breaks will be given. The participants will be offered rest breaks between assessments and trial sets to prevent fatigue and accommodate sensory regulation needs. Video recordings will be used exclusively for evaluation of interrater and intrarater reliability of rater scoring; no repeat participant assessments will be conducted. Interrater reliability will be evaluated by having 6 independent raters score the same recordings. Intrarater reliability will be evaluated by having each rater re-score the same recordings after a 2-5-day interval.

Identification and examination of demographics, perceived physical function, fall risk, health-related QoL, and PA will be conducted in Phase 2 of this study. A summary of the health outcome measures and related ICF domains is presented in Table 1.

All analyses will be conducted using 2-sided tests with a significance level of α=.05. Descriptive statistics will summarize participant characteristics and study variables. Continuous variables will be summarized using means and standard deviations or medians and interquartile ranges, as appropriate, and categorical variables using frequencies and percentages. Prior to inferential analyses, assumptions of normality, linearity, homoscedasticity, and absence of multicollinearity will be evaluated. If the assumptions for parametric analyses are not met, appropriate nonparametric or robust analytic methods will be applied.

Funding for this study was active from August 2024 through May 2025. Participant recruitment was conducted from December 2024 to March 2025, and final data collection was completed in May 2025. As of May 2025, 155 participants had been recruited into the study. Figure 3 summarizes participant recruitment and enrollment. Data analysis is projected to be completed by July 2026, and the primary study results are anticipated to be submitted for publication in August 2026.

Of 544 adults with ASD contacted through the SPARK Registry, 229 responded to invitation emails, and 227 expressed interest in participating (see Figure 3). Following the eligibility screening, 15 individuals were excluded, resulting in 212 eligible participants. Of these, 203 were invited to participate, and 155 ultimately provided electronic informed consent and were enrolled in the study. Among enrolled participants, 101 (65.2%) identified as female, 53 (34.2%) identified as male, and 1 (0.6%) selected rather not to say.

The sample was racially and ethnically diverse: 79 (51.0%) participants identified as Black/African American, 40 (25.8%) as Hispanic, 34 (21.9%) as non-Hispanic White, 1 (0.6%) as Asian, and 1 (0.6%) did not report race/ethnicity. Table 2 presents the participant demographic characteristics.

Data analysis is projected to be completed by July 2026. Submission of the primary results manuscript is anticipated in August 2026.

This study is expected to generate preliminary evidence regarding the feasibility, validity, and equity relevance of remotely administered physical function and balance assessments in adults with ASD. If the planned hypotheses are supported, the study will demonstrate that patient-reported physical function is associated in the expected direction with related indicators of health and physical functioning, including PA, fall risk, lower-extremity functional outcomes, and comorbidity burden. The study is also expected to provide preliminary evidence regarding the reliability of rater scoring of recorded remote performance tasks and the feasibility of telehealth-delivered physical function assessments in adults with ASD.

This protocol represents, to our knowledge, the first attempt to systematically evaluate the reliability and validity of remote, performance-based physical function and balance assessments in adults with ASD. Prior work in other populations supports the relevance of combining patient-reported and performance-based measures. More recently, moderate-to-strong associations were demonstrated between PROMIS-PF and common performance-based measures such as the 5xSTS, Time Up and Go, and 10-Meter Walk Test in outpatient neurologic rehabilitation, highlighting the complementary value of these approaches [44]. However, that study was conducted using retrospective, in-clinic data and did not address feasibility, reliability, or validity in remote assessment contexts or in autistic populations [44]. By adapting standardized assessments for telehealth delivery, the present study addresses an important gap in rehabilitation research for neurodivergent populations and applies a prospective remote-assessment approach. Persistent motor impairments, including deficits in coordination, balance, and gait, remain underresearched in adults with ASD despite their relevance to fall risk, reduced PA, and diminished participation [65]. The protocol is grounded in the MHDD framework, which emphasizes the interaction among health conditions, functional status, activity, participation, and contextual factors in shaping QoL [25]. Within this framework, remote physical function assessment is positioned as a practical approach for identifying modifiable factors that may influence participation, PA, and health equity. Findings from this work are expected to help address the need for standardized, accessible, and psychometrically sound functional assessments that remain relevant across adulthood in ASD [66].

If the planned assessments are found to be feasible and psychometrically supported, this protocol has the potential to inform new models of physical therapy assessment for adults with ASD by enabling clinicians to administer standardized functional measures remotely. Such an approach may reduce barriers associated with transportation, sensory sensitivities, and anxiety, all of which can limit access to in-person services for adults with ASD [67,68]. These barriers may also contribute to reduced PA and increased fall risk. Telehealth-based assessment, combined with wearable activity monitoring, may therefore improve participation in both research and clinical care among individuals who might otherwise be underrepresented or unable to access physical therapy services. In addition, examining the relationship between remotely observed performance and patient-reported outcomes may strengthen clinical interpretation and support more individualized care planning.

A central contribution of this protocol is its focus on health equity. Telehealth delivery aligns with broader efforts to reduce health care disparities among adults with ASD, particularly among racial and ethnic minority groups who often face additional structural barriers to care [69,70]. By evaluating the reliability and validity of remote physical function assessments, this study may help establish a foundation for more scalable and equitable rehabilitation strategies. Remote assessment may be especially beneficial for adults with ASD who experience anxiety, sensory overresponsiveness, or transportation barriers that make clinic-based participation difficult. Conducting assessments within the home environment may reduce these barriers by allowing participation in a setting that is familiar, controlled, and often more tolerable. If the proposed measures demonstrate acceptable performance, they may support more equitable access to observational physical assessments and provide clinicians with alternatives to relying exclusively on questionnaires. This work may also inform future intervention studies aimed at improving PA, physical functioning, and QoL in diverse adult ASD populations.

This protocol has several strengths. First, it integrates patient-reported, behavioral, and remotely observed indicators of physical function into a single telehealth-based study design. Second, it evaluates both construct validity and rating reliability, thereby strengthening the measurement framework for remote assessments in adults with ASD. Third, the protocol explicitly incorporates racial and ethnic disparities in physical function, PA, and QoL, which may inform future equity-focused research and intervention.

Several limitations should also be acknowledged. As a pilot study, the project may be underpowered to detect small effects, particularly in subgroup and moderation analyses. In addition, the sample includes independently living adults with relatively high cognitive abilities, which may limit generalizability to individuals with greater support needs. A further limitation is the overrepresentation of females in the SPARK registry relative to historical ASD diagnosis ratios, although more recent literature suggests that previous estimates of the male-to-female ratio may partly reflect underdiagnosis or delayed diagnosis in females [71-73]. Future studies should prioritize broader representation across sex, racial and ethnic background, cognitive profiles, and levels of required support. Finally, remote performance-based assessments may be influenced by the home environment, camera positioning, technology access, and participant familiarity with telehealth procedures. Accordingly, the primary contribution of this study is expected to be methodological and hypothesis-generating rather than definitive.

This protocol may provide a foundation for integrating telehealth into neurodiverse rehabilitation research and practices. If the planned psychometric and feasibility findings are supported, future studies should replicate these methods in larger and more heterogeneous cohorts, including a greater representation of males, individuals with varying cognitive abilities, and adults with greater support needs. Future studies should also examine the longitudinal relationships between anxiety, perceived fall risk, physical performance, and PA in adults with ASD. In addition, evaluating whether race and ethnicity moderate the relationships among physical function, PA, and QoL may yield important insights for developing more tailored and equity-oriented interventions in the future.

Study findings will be disseminated through peer-reviewed journal publication, conference presentations, and communication with relevant clinical, research, and community stakeholders. The findings from this pilot protocol are also expected to inform future grant applications and the design of larger studies focused on remote physical function assessment, PA, and health equity in adults with ASD.

This protocol describes a pilot study designed to evaluate the feasibility, validity, and equity of remotely administered physical function and balance assessments in adults with ASD. If the planned hypotheses are supported, this study will provide preliminary evidence to guide the use of telehealth-based physical function measures in future research and may inform more accessible approaches to physical therapy assessment in this population. The anticipated contribution of this work is primarily methodological and foundational, with the goal of supporting larger, fully powered studies that can more definitively examine functional health, participation, and QoL in adults with ASD.