Overview
ISO/TR 16840-9:2015 - "Wheelchair seating - Part 9: Clinical interface pressure mapping guidelines for seating" provides best-practice guidance for using interface pressure mapping (IPM) in clinical wheelchair seating evaluations. It addresses the tasks directly involved in clinical IPM use and complementary activities within a comprehensive seating assessment. The report describes the state of the art for IPM in seating scenarios and notes that many principles can be extrapolated to whole-body (in bed) or foot assessments. It is not a replacement for clinical reasoning, nor does it cover taking medical history, prescription, or treatment processes.
Key topics
- Definitions and glossary: calibration, contact area, envelopment, sensor saturation, creep, hysteresis, dispersion index (DI), coefficient of variation (CoV), etc.
- Clinical applications: cushion comparison, wheelchair set-up, client/caregiver education, assessment during dynamic activities, relevance to activities of daily living.
- Test protocol: infection control, mat set-up and orientation, acclimatization of cushions, consistent positioning and settling time, transfer procedures, capturing and validating pressure images.
- Documentation: file naming, storage, photo documentation, reporting, and data backup.
- Interpretation and metrics: isobar/contour (2-D) views, 3‑D surface views, centre of pressure (CoP), pressure gradient, asymmetry measures, interpolation and smoothing methods.
- Limitations: IPM does not reliably predict pressure injuries alone; microclimate, clothing, posture, repeatability, and sampling frequency affect results.
Applications (practical value)
- Cushion selection and comparison: objective comparison of pressure distribution between cushions.
- Wheelchair set-up optimization: fine-tuning seating position, tilt/recline, and support surfaces to reduce high-pressure zones.
- Client and caregiver education: visual feedback to explain risks and demonstrate adjustments.
- Dynamic assessment: monitoring pressure during transfers, propulsion, or daily activities.
- Research and product development: standardized approach for evaluating seating systems and sensors.
Who should use this standard
- Occupational therapists and physiotherapists specializing in seating and pressure care
- Seating clinics and clinicians performing wheelchair assessments
- Rehabilitation engineers and researchers working with pressure mapping technologies
- Manufacturers and product testers of cushions and seating systems
Related standards
- ISO 16840 series (wheelchair seating): Part 1 (vocabulary and measures), Part 2 (cushion mechanical characteristics), Part 3 (static/impact testing) - ISO/TR 16840-9 complements these by focusing on clinical IPM guidelines.
Keywords: ISO/TR 16840-9:2015, interface pressure mapping, IPM, wheelchair seating, pressure mapping guidelines, clinical pressure mapping, cushion assessment, seating evaluation.