Virtual Physical Fitness Assessments for Childhood Cancer Survivors: New Evidence Shows Safe, Effective Home-Based Testing

Table of Contents

1. Key Highlights
2. Introduction
3. Why physical fitness assessment matters after childhood cancer
4. Designing a virtual assessment that works: protocol and practical setup
5. What the MERRIER feasibility study found
6. Which tests translate well to virtual delivery — strengths and limitations
7. Safety, session length and family experience — what mattered
8. Practical guidance for clinicians and program leads
9. Equity, technology and scale: bridging the digital divide
10. Research and validation agenda: what must come next
11. Policy and implementation considerations
12. Limitations and cautions
13. Practical case example: how a clinic might adopt virtual assessments
14. FAQ

Key Highlights

• A supervised, home-based model of six standard physical fitness tests was feasible and safe for childhood cancer survivors aged 5–18: 92.9% completed the full battery, 98.8% of planned assessments were completed, and technique fidelity met protocol standards in 90.9% of completed tests.
• Younger children (approximately 5–7 years) had lower technique fidelity on tests requiring coordination and postural control (sit-to-stand, push-up), indicating the need for age-adapted protocols or closer supervision; no adverse events occurred and median session time was under 20 minutes.

Introduction

Survival from childhood cancer has improved dramatically; five-year survival in high-income countries now approaches 80–85%. That success carries a paradox: most survivors experience late health effects related to their cancer or its treatment, and many face long-term deficits in strength, mobility and cardiorespiratory fitness that increase chronic disease risk. Regular, objective assessment of physical function is central to personalised survivorship care, but practical barriers routinely block access. Families face travel, cost, scheduling, and specialist workforce shortages — especially those who live outside major cities.

A feasibility sub-study nested within the MERRIER trial tested whether live, virtually supervised physical fitness assessments could safely, reliably and acceptably be conducted in survivors’ homes. The study offers concrete data on recruitment, completion rates, technique fidelity, safety, session duration and family experience. Results indicate that a clinician-supervised telehealth model can deliver repeatable functional measures across six tests with high completion and strong participant satisfaction. This article synthesises the study findings, examines implications for clinics and families, and outlines practical guidance for implementing virtual assessment in paediatric oncology follow-up.

Why physical fitness assessment matters after childhood cancer

Treatments that cure childhood cancer also change the body. Chemotherapy agents such as anthracyclines carry cardiotoxic risk; radiotherapy and prolonged steroid exposure can impair bone health, muscle development and metabolic function. Survivors commonly face reduced cardiorespiratory fitness, lower muscular strength and balance impairment. These deficits reduce quality of life, limit participation in everyday activities and increase long-term cardiovascular and metabolic risk.

Physical fitness measurement serves three principal clinical purposes:

• Identify deficits that require targeted rehabilitation or medical review.
• Provide objective baselines for individualised exercise prescription and progress monitoring.
• Flag at-risk patients for early intervention to reduce late morbidity.

Despite this clinical imperative, routine objective testing is inconsistent. Many survivorship clinics lack on-site exercise specialists, and families face logistical hurdles attending in-person assessments. Embedding reliable, low-burden fitness assessment into survivorship pathways would bring functional monitoring within reach for more families. The feasibility findings from the MERRIER baseline sub-study point to a pragmatic model for achieving that.

Designing a virtual assessment that works: protocol and practical setup

The study created a compact, replicable protocol to translate clinic-style functional tests to the home setting under live supervision.

Participants and screening

• Eligible children were aged 5–18, had completed intensive cancer therapy (maintenance chemotherapy permitted), and were cleared for activity using a pre-exercise screening tool (PSS-YP) administered by telephone. Contraindications (eg, cardiomyopathy, uncontrolled arrhythmias) excluded participation.

Assessment platform and supervision

• Assessments were performed via Microsoft Teams with real-time supervision by an Accredited Exercise Physiologist (AEP). Parents received guidance on camera positioning and were present to provide safety oversight when needed.

Preparation materials and equipment

• Families were emailed pre-recorded instruction videos, an equipment checklist and an infographic covering setup and safety. A small study pack sent to homes included a ruler and a 3 m pre-cut rope to standardise components of the sit-and-reach and timed up-and-go tests.

Test battery and delivery

• Six assessments targeted lower- and upper-body strength, mobility, balance, flexibility and aerobic endurance: sit-to-stand (30 s), timed up-and-go (mean of two trials), single-leg balance (eyes open/closed), push-up (30 s; full or knee-supported), sit-and-reach, and the two-minute step test. Tests were selected for clinical relevance, minimal equipment needs and prior evidence of virtual feasibility in related populations.
• Sessions followed a semi-standardised order beginning with sit-to-stand and ending with the two-minute step test; clinicians adapted order for fatigue, equipment availability and child preference.

Technique fidelity and data capture

• The supervising AEP judged technique fidelity during live observation against a predefined checklist. Assessments were only scored if repetitions met protocol standards; tests were discontinued if correct technique could not be achieved safely after repeated instruction. Data were entered directly into REDCap and videos were re-scored by two team members to minimise transcription error.

This practical design emphasised safety, standardisation and low participant burden — key considerations for scaling a virtual model across diverse households.

What the MERRIER feasibility study found

Sample and recruitment

• Recruitment was successful: 43 families submitted expression of interest and 29 enrolled; 28 completed assessments and formed the analysis cohort. Twenty-three participants enrolled within the first three months, surpassing the predefined benchmark (≥15).
• Participants (n = 28) had mean age 9.8 years (SD 3.7), 61% male, with acute lymphoblastic leukaemia comprising 46% of diagnoses. All had received chemotherapy; many had surgery (61%) and radiotherapy (39%). Most families lived in metropolitan areas (89%).

Feasibility benchmarks and observed outcomes

• Assessment battery completion: 26/28 (92.9%) completed the full six-test battery (benchmark ≥85%).
• Individual assessment completion: 166/168 planned assessments were completed (98.8%; benchmark ≥90%).
• Technique fidelity: 151 of 166 completed assessments (90.9%) met predefined correctness criteria (benchmark ≥85%).
• Session duration: median 19.5 minutes (range 15–33); 26/28 (92.9%) sessions were ≤30 minutes (benchmark ≥90%).
• Safety: zero serious or minor adverse events.

Test-specific performance

• Timed up-and-go: completion 100%; technique fidelity 92.9% (26/28).
• Sit-to-stand: completion 100%; fidelity 89.3% (25/28).
• Sit-and-reach: completion 100%; fidelity 89.3% (25/28).
• Single-leg balance: completion and fidelity 100% (28/28).
• Two-minute step: completion and fidelity 100% (28/28).
• Push-up: completion 92.9% (26/28); fidelity lower at 73.1% (19/26).

Age and fidelity

• Child age positively correlated with overall technique fidelity (Spearman’s ρ = 0.61, p < 0.001). Younger children (median 5–7 years) were more likely to fail to meet correct technique on the sit-to-stand and push-up tests.

Acceptability

• Nine families provided open-ended feedback. Themes: convenience (less travel, flexible scheduling), better child engagement in familiar environments, sessions described as “easy,” “fun,” and “great,” and perceived motivational benefits for ongoing physical activity. Representative comments included “Would rather do it at home over a hospital any day of the week” and “That was perfect—really fun actually.”

Exploratory patterns

• Time since treatment showed a positive but non-significant association with fidelity (ρ = 0.32, p = 0.092), suggesting that children further from treatment completion may perform better, though larger samples are required to confirm this signal.

These outcomes demonstrate that a clinician-led, virtually supervised assessment model can produce high completion, strong fidelity and rapid testing with minimal safety concerns in a post-treatment paediatric oncology cohort.

Which tests translate well to virtual delivery — strengths and limitations

The study’s six-test battery was deliberately compact and practical for home administration. The results reveal which measures adapt smoothly to telehealth oversight and which present challenges that require adaptation.

Best-translating measures

• Single-leg balance and two-minute step test performed consistently well with perfect completion and fidelity. These tasks are straightforward to observe on camera, have clear pass/fail criteria and require minimal supervised feedback beyond initial setup. The single-leg balance test’s short duration and clear termination rules minimise risk.
• Timed up-and-go and sit-and-reach also translated well. Both have established protocols that can be standardised through camera setup and simple household markers (eg, a 3 m rope for the walking distance). Timed up-and-go benefits from being time-based rather than repetition-scored, reducing scoring ambiguity.

Measures requiring adaptation

• Push-up test posed the greatest challenge. Although a knee-supported modification was allowed, fidelity was 73.1% among completed push-up attempts. Push-ups require coordinated trunk and shoulder control, consistent range of motion and a stable camera perspective to judge technique. Younger children also struggled with form and pacing.
• Sit-to-stand had slightly lower fidelity than some other tests (89.3%) and reflects the combined demands of timing, consistent chair height and trunk control. Younger children sometimes used compensatory strategies that altered movement biomechanics and invalidated repetitions.

Age considerations

• The positive correlation between age and fidelity indicates developmental capacity matters. Younger school-aged children may require:
  • Additional pre-session demonstration and practice attempts.
  • Simpler, child-friendly instructions and visual cues.
  • Shorter, interactive sessions with more breaks or parent-led physical prompts.
  • Potential substitution of demanding tests with alternative assessments (for example, substituting a push-up with an upper-body endurance measure that better fits developmental ability).

Practical scoring tips

• Use household markers and simple equipment to standardise distances and heights (supplied ruler, tape measure, pre-cut rope).
• Require parents to stabilise the camera at an angle that captures the whole body and test area; use screenshots or short video clips to allow secondary scoring checks.
• Train assessors to recognise common compensatory movements and to prompt for repetition only when technique conforms to protocol.

Overall, tests that are simple to observe, low-risk and require minimal environmental standardisation are best suited for remote delivery. Tasks that combine complex multi-joint coordination and require fine-grained visual assessment will need additional supervision strategies or in-person verification for younger children.

Safety, session length and family experience — what mattered

Safety

• The absence of adverse events across 28 supervised sessions suggests that clinician-led virtual testing can be conducted with low immediate risk when appropriate screening and real-time oversight are in place.
• Key safety enablers in the protocol included pre-session screening (PSS-YP), live AEP supervision, parent presence for physical oversight, and stopping rules for tests that could not be performed safely.

Session length and workflow efficiency

• Median session length under 20 minutes and most sessions completed in ≤30 minutes point to a low time burden for families and clinicians. This efficiency supports integration into routine survivorship contacts or telehealth follow-ups without requiring major scheduling resources.

Family-centered benefits

• Families valued the convenience of home testing, reporting reduced travel burden, less disruption to daily life and improved child cooperation in familiar settings. Several parents indicated the sessions prompted renewed motivation for physical activity and offered an opportunity for family participation.
• Practical benefits extend beyond convenience. For some families, remote testing reduces logistical barriers that have historically limited access to exercise assessment and rehabilitation services, particularly when adult caregivers must juggle multiple appointments.

Operational enablers of good experience

• Pre-recorded instructional media and mailed equipment packs prepared families and reduced in-session setup time.
• Real-time feedback from an accredited clinician provided reassurance to parents and helped children perform tasks correctly.
• Community partnership (Camp Quality) facilitated early engagement by connecting the research team with families through trusted networks.

These elements combined to produce a model that is safe, efficient and acceptable to the subset of families who engaged in the study. The challenge for broader implementation will be extending these benefits equitably across socio-economic and geographic contexts.

Practical guidance for clinicians and program leads

Translating these feasibility findings into routine practice requires operational checklists and training. The following practical steps synthesise study methods into actionable recommendations.

Before the session

• Screening: Use a validated pre-exercise screening (eg, PSS-YP) administered by telephone to identify contraindications. Confirm current treatment status and recent medical events.
• Consent and information: Provide written information and obtain informed consent. Supply a clear schedule and expectations for equipment, clothing and location.
• Equipment pack and materials: Send or list essential items: stable armless chair (~43 cm seat height if possible), ruler or tape measure, 3 m marker (tape or rope), smartphone or tablet with video, clear floor space and comfortable clothing. Pre-cut rope and ruler reduce measurement variability.
• Pre-session media: Share short instructional videos and a one-page infographic with setup pictures and camera-angle guidance.

Camera and environment setup

• Camera angle: Position the device to capture the full body and testing area; for standing tests, an oblique angle slightly elevated from floor level helps. Parents can use a stack of books to stabilize a tablet or phone.
• Lighting and background: Ensure even lighting and minimal glare. Remove rugs or obstacles that might create slip hazards.
• Supervision: An adult should be physically present to monitor safety and comply with clinician guidance.

During the session

• Warm-up: Begin with a brief active warm-up: marching in place or ankle, hip and shoulder mobility for 1–2 minutes.
• Instruction and demonstration: Provide a live demonstration followed by a practice trial where appropriate, especially for younger children.
• Technique checks: Count only repetitions performed with correct technique. Use standard verbal cues and one or two corrective prompts if faults occur.
• Stopping rules: Discontinue any test if pain, symptom exacerbation or unsafe movement occurs. If correct technique cannot be achieved safely after instruction, discontinue and record as invalid.
• Data recording: Enter scores immediately in the electronic data system and save short video clips for secondary review or audit.

Test-specific adaptations

• Push-ups: Allow knee-supported variation for younger or weaker children. If technique remains non-compliant, substitute with a clinically meaningful upper-body alternative (eg, seated shoulder press with minimal load or handgrip dynamometry if available).
• Sit-to-stand: Confirm chair height and foot placement. Younger children may need visual targets or prompts for trunk alignment.
• Two-minute step: Define knee-height target using anatomic landmarks and count right-leg steps; capture hands-free with a stable camera angle for counting accuracy.

Post-session

• Debrief: Provide immediate feedback, reinforcing strengths and highlighting areas for home exercise focus.
• Follow-up plan: Use results to prescribe individualised exercise or refer to physiotherapy/rehab as needed.
• Data security: Store video and assessment data in secure, regulator-compliant systems and obtain consent for recording and retention.

Training and workforce

• Train AEPs and allied health professionals on virtual assessment protocols, camera coaching, and common home-environment fixes.
• Create standard operating procedures and fidelity checklists to align scoring across clinicians.

Billing and documentation

• Record assessments in clinical notes and, where available, bill using telehealth or allied health item numbers. Advocate with local payers for recognition of telehealth functional assessments as reimbursable clinical services.

These recommendations synthesise operational detail into an implementable pathway for clinics seeking to add virtual fitness assessments into survivorship care.

Equity, technology and scale: bridging the digital divide

Virtual models expand reach but do not automatically close access gaps. The study cohort was predominantly metropolitan and likely more digitally enabled than the wider survivor population. Scaling virtual assessment requires deliberate strategies to address technology, connectivity and social determinants.

Barriers to equity

• Internet connectivity: Rural and remote families often lack stable broadband or sufficient upload speeds to support real-time video.
• Device access: Not all households have a camera-enabled tablet or smartphone with a large enough screen to capture full-body movement.
• Digital literacy: Some caregivers may be unfamiliar with videoconferencing platforms or camera positioning.

Practical measures to reduce inequities

• Low-bandwidth options: Offer phone-based coaching with pre-recorded videos and asynchronous video uploads when live connectivity is poor. Asynchronous assessments carry trade-offs in immediacy and safety oversight but may increase participation.
• Device lending programs: Partner with charities, hospital foundations or community organisations to provide temporary loan devices for families without suitable hardware.
• Technical support: Provide pre-session test calls, printed setup instructions, and a helpline to troubleshoot connectivity and camera issues.
• Community partnerships: Use trusted local organisations, like Camp Quality in the study, to recruit and support families who may otherwise be hard to reach.
• Hybrid models: Combine an early in-person baseline visit with virtual follow-up for families with limited digital access, reducing travel frequency while ensuring accurate baseline measures.

Technology enhancements to support scaling

• Wearables and activity monitors: Objective activity data from wrist-worn accelerometers and step counters can complement periodic functional testing by capturing habitual behaviour and recovery trajectories.
• Automated scoring: Emerging AI-based pose estimation tools can assist in movement scoring and reduce assessor burden. The study cited the PLATINUMS project as an example of AI telerehabilitation development; similar tools could flag gross errors or provide secondary scoring for selected tasks.
• Secure platforms: Use clinician-approved videoconferencing tools that meet privacy and health-information regulatory standards.

Program-level considerations

• Build equity metrics into program evaluation and target outreach to under-served regions.
• Track participation by socio-economic status, geographic remoteness and language to identify digital exclusion and design targeted supports.

Virtual assessments have the potential to increase reach but only if programs actively mitigate structural barriers. Equity must be baked into service design rather than assumed as a byproduct of technology.

Research and validation agenda: what must come next

Feasibility is the necessary first step. Several next-phase research priorities will determine whether virtual assessments can be widely adopted in clinical practice.

Validation against in-person gold standards

• Concurrent validity studies are required comparing virtual and face-to-face performance on each test to quantify measurement equivalence, systematic bias and limits of agreement.
• Test–retest reliability studies in the same digital format will document measurement stability over time.

Larger, more diverse samples

• Multicentre trials should include wider age ranges, larger samples, and greater representation from regional, rural and socioeconomically disadvantaged populations.
• Stratified analyses will identify subgroups for whom virtual assessments require adaptation or in-person verification.

Age-adapted protocols

• Establish age-specific norms or modified test versions for younger children. The current study suggests young children struggle with certain tests; research should define alternative measures that maintain clinical relevance.

Automated and hybrid scoring methods

• Evaluate AI-based pose estimation for feasibility, accuracy and clinical acceptability. Automated tools might reduce assessor workload and enable asynchronous scoring for families with limited live access.
• Explore hybrid models combining an initial in-person baseline with virtual follow-ups to balance measurement precision and accessibility.

Outcome linkage and clinical utility

• Prospective studies should link assessment results to clinical outcomes (eg, functional status, return to school/sports, cardiometabolic markers) to establish predictive validity and demonstrate utility for clinical decision-making.

Implementation science studies

• Investigate real-world adoption in routine survivorship clinics, including clinician workflows, reimbursement models and cost-effectiveness.
• Use qualitative and participatory methods to understand family experience, barriers to sustained participation and acceptability across cultural contexts.

Standardisation and consensus

• Convene expert panels to develop consensus-based protocols for virtual assessment set-up, camera angles, equipment standards, scoring rules and safety procedures, analogous to clinical test manuals used in laboratory settings.

This research agenda will transform feasibility evidence into validated, standardised tools that clinicians can adopt with confidence.

Policy and implementation considerations

Scaling virtual functional assessment into survivorship care requires alignment across clinical, technological and policy domains.

Telehealth reimbursement and funding

• Clear, sustainable reimbursement mechanisms for clinician-supervised virtual assessments are essential. Policymakers and payers should recognise the value of functional assessment as a core clinical activity.
• Funding for device lending, broadband subsidies and digital literacy programs can reduce barriers to access.

Workforce development

• Training programs and continuing professional development should equip AEPs, physiotherapists and allied health staff with virtual assessment skills, camera coaching techniques and telehealth safety protocols.

Integration into survivorship pathways

• Embed functional testing schedules within survivorship care plans: eg, baseline at treatment completion, periodic follow-up at 6–12 month intervals or when clinically indicated.
• Use virtual assessments to triage referrals to in-person rehabilitation, physiotherapy or cardiology when deficits are detected.

Partnerships with community organisations

• Collaborate with charities and community groups for outreach, device provision and co-design of family-centred services. The study’s partnership with Camp Quality helped recruitment and engagement, illustrating the value of trusted networks.

Data governance and privacy

• Standardise policies for video recording, data retention and consent. Ensure encrypted storage and clear parental consent for any recorded material.

Equity and quality metrics

• Monitor participation and outcomes across demographic groups to ensure virtual services do not exacerbate health inequities.
• Establish quality indicators such as completion rates, fidelity benchmarks and time-to-assessment, and report these transparently.

Policy alignment and sustained funding will determine whether virtual assessment moves from an experimental offering to an established feature of survivorship care.

Limitations and cautions

The feasibility outcomes are encouraging but must be interpreted within the study’s limits.

Selection bias

• Recruitment through a childhood cancer charity likely engaged families who were motivated and digitally literate. Results may overestimate general population acceptability and completion.

Sample composition

• The cohort was small (n = 28) and predominantly metropolitan. Rural and socioeconomically disadvantaged families were under-represented.

Lack of concurrent in-person comparator

• Without an in-person reference, validity and systematic bias cannot be assessed. Feasibility does not imply measurement equivalence.

Observer and environmental variability

• Technique fidelity was assessed by a single rater; observer bias is possible. Home environments vary in chair height, lighting, camera angle and surface, which can affect scoring.

Age heterogeneity

• Wide age range (5–18) spans developmental differences that influence test suitability. Younger children showed lower fidelity on some measures.

Limited qualitative depth

• Acceptability feedback was collected opportunistically from nine families and may not capture broader user experience or acceptability barriers.

These limitations point to the need for larger validation studies that include in-person comparisons, blinded scoring, and diverse samples before virtual assessments are adopted as standalone clinical measures.

Practical case example: how a clinic might adopt virtual assessments

A mid-sized paediatric oncology survivorship clinic piloting a virtual assessment program could follow this sequence:

1. Establish governance: secure institutional telehealth platform, data storage, consent templates and clinician training.
2. Pilot cohort: recruit 30 survivors across ages 7–16, prioritising families with travel burdens.
3. Pre-screen: telephone PSS-YP and technical check call; ship equipment packs to consenting families.
4. Schedule half-hour sessions: AEP conducts a 20-minute assessment via Teams, records short clips for quality audit.
5. Immediate feedback: clinician provides a one-page report and tailored home-exercise suggestions; flags any clinical concerns to the oncology team.
6. Evaluation: collect completion rates, technique fidelity, family satisfaction and clinician time costs. Compare with a control group attending in-person assessments if feasible.
7. Scale and refine: add asynchronous options for limited-bandwidth families and partner with local charities for device lending.

This staged approach mirrors the methods and lessons from the MERRIER feasibility study and balances patient safety, measurement quality and access.

FAQ

Q: Are virtual fitness assessments safe for childhood cancer survivors? A: With appropriate pre-screening, real-time clinician supervision, parent oversight and stopping rules, the MERRIER feasibility study reported no adverse events. Safety protocols are essential and should be part of any virtual program.

Q: Which tests work best at home? A: Single-leg balance, two-minute step, timed up-and-go and sit-and-reach translated reliably to the home setting. Tests that require precise multi-joint coordination, like push-ups, were more challenging—especially in younger children—and may need modifications or alternatives.

Q: Will virtual assessments give the same results as in-person testing? A: Feasibility does not equal validated equivalence. The study showed high completion and fidelity but did not include concurrent in-person comparison. Future validation studies are needed to establish measurement equivalence and quantify any systematic differences.

Q: What age range is appropriate for virtual testing? A: The study included 5–18-year-olds. Younger children (5–7 years) had lower technique fidelity on some tests. Clinics may consider tailoring test batteries by age or adding more in-session practice and caregiver coaching for younger children.

Q: What equipment do families need? A: Minimal items: a stable armless chair, a ruler or tape measure, a 3 m marker (rope or tape), suitable clothing and a camera-enabled device. Study teams can supply basic tools and instructional media to standardise test setup.

Q: How long does a virtual assessment take? A: Median session time was 19.5 minutes; most sessions were completed in 30 minutes or less. Short sessions reduce family time burden and fit into telehealth workflows.

Q: How should clinicians handle poor internet connectivity? A: Offer alternative workflows: pre-recorded instructional videos with asynchronous video uploads, phone coaching, or arrange hybrid visits where an initial in-person baseline is conducted and follow-ups are virtual. Device lending and local community support can also help.

Q: Can automated tools replace clinician scoring? A: Automated pose-estimation and AI scoring hold promise to reduce assessor burden and increase standardisation, but they require validation in paediatric oncology contexts prior to replacing clinician supervision.

Q: How can virtual assessment programs reach families in rural or disadvantaged communities? A: Combine technical support, low-bandwidth options, device-lending programs, partnerships with community organisations and hybrid models integrating occasional in-person contact with mostly virtual follow-up.

Q: When should a child be referred for in-person assessment or rehabilitation? A: Use virtual testing to stratify risk: flagged deficits, significant asymmetry, pain during testing, or inconsistent technique that suggests underlying impairment should prompt in-person evaluation or referral to physiotherapy or specialist care.

Q: Is reimbursement available for virtual fitness assessments? A: Reimbursement varies by jurisdiction. Clinicians should document clinical intent and align services with telehealth billing policies. Advocacy for recognition of supervised virtual functional assessment as a reimbursable service will support wider adoption.

Q: What are the next research steps? A: Priority actions include validation studies comparing virtual and in-person assessments, larger multicentre reliability trials, age-specific protocol development, evaluation of automated scoring tools, and implementation research focusing on equity and cost-effectiveness.

Q: How can families prepare their child for a virtual assessment? A: Ensure a quiet, well-lit space with a cleared floor area, comfortable clothing and shoes (or bare feet for flexibility tests). Review pre-session videos, position the camera to capture full body, and have a parent present to help with setup and safety.

Q: Where can clinicians find standard protocols and training materials? A: Adapt the study’s core elements: pre-exercise screening, short instructional videos, standardised equipment lists, fidelity checklists and stopping rules. As consensus protocols emerge from future research, professional bodies and paediatric oncology networks will be key dissemination channels.

The MERRIER feasibility sub-study demonstrates that clinician-supervised virtual physical fitness assessments are a viable option for many childhood cancer survivors. Careful attention to screening, setup, age-appropriate protocols and equitable access strategies will determine whether the model can move from pilot projects to routine survivorship care.