TABLE 1.

Comparison of validation protocols for blood pressure (BP) measuring devices.

	BHS (3)	Quality seal protocol -DHL (4)	ESH IP2 (5)	ANSI/AAMI/ISO (7)	AAMI/ESH/ISO (8)
Organization	British Hypertension Society	German Hypertension League	European Society of Hypertension	American National Standards Institute/Association for the Advancement of Medical Instrumentation/ International Organization for Standardization Collaboration	Association for the Advancement of Medical Instrumentation/ European Society of Hypertension/ International Organization for Standardization Collaboration
Last revision	1993	1999	2010	2013	2018
Sample size	85	96	33	≥85	≥85
Participants’ age	15–80 years	>20 years	≥25 years	>12 years	> 12 years
Age distribution	By chance	3 age groups Distribution based on age and SBP and DBP levels	By chance	By chance	By chance
Sex distribution	By chance	Equally represented	≥10 subjects of each sex	≥30% of each sex	≥30% of each sex
Arm circumference distribution	By chance	By chance	By chance	Single cuff: ≥40% in the upper/lower half of the specified cuff-range ≥20% in the upper/lower quarter. Multiple (n) cuffs: each cuff at least 1/(2 × n) of the subjects	Single cuff: ≥40% in the upper/lower half of the specified cuff-range ≥20% in the upper/lower quarter, ≥10% within the upper/lower octile Multiple (n) cuffs: each cuff at least 1/(2 × n) of the subjects
BP range distribution	SBP (mmHg) <90: ≥8 subjects, 90–129: ≥20, 130–160: ≥20, 161–180: ≥20, >180: ≥8, DBP (mmHg) <60: ≥8 subjects, 60–79: ≥20, 80–100: ≥20, 101–110: ≥20, >110: ≥8	20–40 years SBP (mmHg): ≤140:12 subjects ≥141:12 DBP (mmHg): ≤90:12 ≥91:12 41–70 years: SBP: ≤120:8 121–140:16 141–160:16 ≥ 161:8 DBP: ≤80:8 81–90:16 91–100:16 ≥101:8 ≥71 years: SBP: ≤140:12 >141:12 DBP: ≤90:12 >91:12	SBP (mmHg) <130:10–12 subjects, 130–160:10–12, >160 mmHg: 10–12 DBP (mmHg) <80:10–12, 80–100:10–12, >100:10–12	SBP (mmHg) ≤100 mmHg: ≥5% of readings ≥140 mmHg: ≥20% ≥160: ≥5%, DBP (mmHg) ≤60 mmHg: ≥5% ≥85 mmHg: ≥20% ≥100 mmHg: ≥5%	SBP (mmHg) ≤100 mmHg: ≥5% of readings ≥140 mmHg: ≥20% ≥160: ≥5%, DBP (mmHg) ≤60 mmHg: ≥5% ≥85 mmHg: ≥20% ≥100 mmHg: ≥5%
Reference BP measurement	Mercury sphygmomanometer	Mercury sphygmomanometer	Mercury sphygmomanometer	Mercury sphygmomanometers or non-mercury auscultatory device with maximum error ± 1 mmHg	Mercury sphygmomanometers or accurate non-mercury devices with maximum error ± 1 mmHg
Measurement method	Same arm sequential BP measurement	Same arm sequential BP measurement	Same arm sequential BP measurement	Same-arm sequential or simultaneous (same or opposite arm) BP measurement	Same arm sequential BP measurement
Paired BP measurements	255	≥288	99 (22–44 in each BP range)	255	255
Specific guidelines for ABPM	Yes	No	No	Yes (separate validation protocols)	Yes (separate validation protocols)
Pass criteria	Grading system (A, B, C, D) based on differences between paired readings by ≤ 5, 10, 15 mmHg separately for each observer and separately for SBP and DBP Additionally, mean differences ≤ 5 mmHg and SD ≤ 8 mmHg (AAMI recommendations)	Criteria based on mean difference and SD and point system for individual paired SBP and DBP readings Pass if the device fulfills all the following criteria: mean difference for SBP and DBP ≤ 5 mmHg and the SD ≤ 8 mmHg and point score ≥ 55% of the maximum attainable point score.	Criteria based on the number of readings with test-reference BP difference ≤ 5, 10, 15 mmHg Criteria for individual BP measurements (Part 1) individual subjects (Part 2) Part 1: Pass if 73.7% (73/99) of differences between readings: ≤ 5 mmHg, 87.9% (87/99) ≤ 10 mmHg, 97.6% (96/99) ≤ 15 mmHg Part 2 (Accuracy): number of subjects with 0, 2 or 3 of absolute difference ≤ 5 mmHg	Criteria based on mean BP differences and their SDs Criteria for individual BP readings and individual subjects. Criteria 1 and 2 should be applied for SBP and DBP Criterion 1 (for individual BP readings): The mean BP difference ≤ 5 mmHg and SD ≤ 8 mmHg Criterion 2 (for individual subjects): The mean difference and SD of BP readings within threshold defined by mean value of criterion 1	Criteria based on mean BP differences (test vs. reference) and their SDs Criteria for individual BP readings and individual subjects. Criteria 1 and 2 should be applied for SBP and DBP Criterion 1 (for individual BP readings): The mean BP difference ≤ 5 mmHg and SD ≤ 8 mmHg. Criterion 2 (for individual subjects): The mean difference and SD of averaged BP differences must be within a threshold defined by mean value of criterion 1 Additionally, the number of absolute BP differences within 5, 10, and 15 mmHg (ESH-IP2) and standardized Bland–Altman scatterplots will be presented The mean test-reference BP difference and SD per cuff subgroup must be reported without pass/fail criteria for the test device
Special groups	Pregnant women, elderly, and children Only if a device has successfully completed all phases of Part I and has achieved at least a B grading for accuracy for both SBP, DBP (Part II.I)	Pregnant women, diabetics, arm circumference > 33 cm	No specific guidelines Separate studies recommended for special populations	Pregnant women, neonates and children, heart irregularities/disease	Children < 3 years, pregnancy including preeclampsia, arm circumference > 42 cm, atrial fibrillation Possible special groups: individuals aged 12–21 or >80 years and those with end-stage kidney disease Special population studies with smaller sample sizes should be performed only after a full general population study has been successfully completed. If the device is intended only for a special population, then a full 85-subject study is required
Special occasions	During exercise and in various postures. Only if a device has successfully completed all phases of Part I and has achieved at least a B grading for accuracy for both SBP, DBP (Part II.II)	No specific guidelines	No specific guidelines	During exercise	No specific guidelines
Extra	Examines intradevice variability, accuracy of devices after long term period of performance

BP, blood pressure; SBP, systolic blood pressure; DBP, diastolic blood pressure; ABPM, ambulatory blood pressure monitoring; SD, standard deviation.