Overview
ISO 81060-2:2018/AMD2:2024 is Amendment 2 to ISO 81060-2 (Non‑invasive sphygmomanometers - Part 2), updating clinical investigation requirements for intermittent automated blood‑pressure measurement devices. Published in 2024, this amendment refines subject-use rules, limb/cuff distribution requirements, minimum measurement counts, and clinical‑reporting expectations to improve accuracy and repeatability in device validation.
Key topics and technical requirements
- Scope clarification
- Cuff sets that differ in materials or construction (e.g., disposable vs reusable, single vs dual hose) are not interchangeable; each cuff set must be evaluated separately.
- Subject eligibility and use
- All subjects in a clinical investigation must be unique; a subject may be used only once.
- Per‑patient measurement counts
- Each patient must have at least 5 and no more than 10 valid blood‑pressure measurements.
- Limb size (cuff) distribution
- The amendment tightens requirements on how subjects are distributed across cuff limb‑circumference ranges.
- For cuff ranges ≤12 cm: at least 40% of subjects in the upper half and 40% in the lower half of the cuff’s specified range.
- For cuff ranges >12 cm and ≤16 cm: at least 20% of subjects in each quartile.
- For cuff ranges >16 cm: at least 20% in each quartile plus 10% in the highest and lowest octiles.
- For multi‑cuff studies, overlap of cuff ranges is limited by a specified formula (see amendment for the exact formula). The amendment provides Formula (18) and Formula (19) to calculate the required number of subjects per cuff and sets minimum subject counts (see clauses 5.1.4 and 6.1.4 for different minimums).
- Clinical investigation reporting
- Reports must specify arm‑circumference ranges for each cuff.
- Include plots of device minus reference BP versus arm circumference (distinct symbols/colors per cuff and vertical lines for cuff limits).
- Include Bland–Altman plots (differences vs averages) for systolic and diastolic BP; if the device reports mean arterial pressure (MAP), include MAP plots as well.
Applications and users
- Who uses this standard
- Medical device manufacturers (design verification and regulatory clinical validation)
- Clinical researchers running validation studies
- Notified bodies and regulators assessing conformity for CE/market clearance
- Independent test laboratories and clinical trial sites
- Quality and regulatory affairs teams preparing submission dossiers
- Practical value
- Ensures robust, reproducible clinical validation of automated sphygmomanometers across realistic arm sizes and cuff designs.
- Reduces risk of inaccurate BP measurement due to improper cuff selection or inadequate sampling.
Related standards
- ISO 81060 series (other parts addressing device performance and requirements)
- Developed jointly with IEC/TC 62 and in liaison with CEN (see full amendment for committee references and implementation guidance).
Keywords: ISO 81060-2:2018/AMD2:2024, non-invasive sphygmomanometer, clinical investigation, cuff size distribution, blood pressure device validation, Bland-Altman plots, limb circumference, automated sphygmomanometer.