Table 2.
BHS grade of agreement between noninvasive and direct-invasive methods: cumulative percentage of absolute difference (mmHg) between IBP and other studied methods (ABP and OBP). Grades are derived from percentages of readings within 5, 10, and 15 mmHg: to achieve a grade, all three percentages must be equal to or greater than the tabulated values. For example, to achieve the “A” grade, sixty percent of the measured BP values with IBP and ABP must be within 5 mmHg, 85% within 10 mmHg, and 95% within 15 mmHg. The limit of ≤20 mmHg does not belong to the BHS criteria and has been inserted to highlight in particular the poor agreement for SAP.
| ≤5 mmHg | ≤10 mmHg | ≤15 mmHg | ≤20 mmHg | BHS grade | |
|---|---|---|---|---|---|
| IBP versus ABP | |||||
| Systolic | 31% | 53% | 63% | 77% | D (very poor) |
| Diastolic | 51% | 76% | 94% | 98% | B (good) |
| Mean | 50% | 85% | 97% | 99% | B (good) |
| IBP versus OBP | |||||
| Systolic | 20% | 40% | 63% | 74% | D (very poor) |
| Diastolic | 62% | 91% | 96% | 99% | A (very good) |
| Mean | 40% | 72% | 96% | 100% | C (poor) |
IBP: invasive blood pressure; ABP: auscultatory-aneroid blood pressure; OBP: oscillometric automated blood pressure; BHS: British Hypertension Society.