The following tables come from the source referenced below.
Empirically-evaluated potential sources of inaccuracy in the measurement of adults’ resting blood pressure
| Range of reported significant mean effects (in mmHg) unless specified | ||
| Potential source of inaccuracy | SBP | DBP |
| Patient-related | ||
| 1. Acute meal ingestion | −6a | −5 to −1.9 |
| 2. Acute alcohol use | −23.6 to +24 | −14 to +16 |
| 3. Acute caffeine use | +3 to +14 | +2.1 to +13 |
| 4. Acute nicotine use or exposure | +2.81 to +25 | +2 to +18 |
| 5. Bladder distension | +4.2 to +33 | +2.8 to +18.5 |
| 6. Cold exposure | +5 to +32 | +4 to +23 |
| 7. Paretic arm | +2a | +5a |
| 8. White-coat effect | −12.7 to +26.7 | −8.2 to +21 |
| Device-related | ||
| 9. Device model bias | ||
| Mercury models | ||
| vs. invasive criterion | −10.6 to −4 | +1.9 to +4 |
| Aneroid models | ||
| vs. invasive criterion | −9.7 to −4.0 | +5.1a |
| vs. noninvasive criterion | −0.8a | −1.7a |
| Automated models | ||
| vs. invasive criterion | −23 to +6 | −3 to +5.6 |
| vs. noninvasive criterion | −3.7 to +16.53 | −8 to +9.71 |
| 10. Device calibration error | ||
| Mercury | 0–61.8% of individual devices > ±3 mmHg calibration error | |
| Aneroid | 1.4–69.7% of individual devices > ±3 mmHg calibration error | |
| Automated | 4.5–26% of individual devices > ±3 mmHg calibration error | |
| Procedure-related | ||
| 11. Insufficient rest period | +4.2 to +11.6 | +1.8 to +4.3 |
| 12. Body position | ||
| Standing | −2.9 to +5 | +7a |
| Supine | −10.7 to +9.5 | −13.4 to +6.4 |
| 13. Legs crossed at knees | +2.5 to +14.89 | +1.4 to +10.81 |
| 14. Unsupported back | No significant effects reported | +6.5a |
| 15. Unsupported arm | +4.87a | +2.7 to +4.81 |
| 16. Arm lower than heart level | +3.7 to +23 | +2.8 to +12 |
| 17. Incorrect choice of cuff size | ||
| Smaller cuff | +2.08 to +11.2 | +1.61 to +6.6 |
| Larger cuff | −3.7 to −1.45 | −4.7 to −0.96 |
| 18. Cuff placed over clothing | No significant effects reported | No significant effects reported |
| 19. Stethoscope under cuff | +1.0 to +3.1 | −10.6 to −3.5 |
| 20. Talking during measurement | +4 to +19 | +5 to +14.3 |
| 21. Use of stethoscope bell (vs. diaphragm) | −3.8 to +1.54 | −1.61a |
| 22. Excessive pressure on stethoscope head | No significant effects reported | −15 to −9 |
| 23. Fast cuff deflation rate | −9 to −2.6 | +2.1 to +6.3 |
| 24. Short interval between measurements | No significant effects reportedb | No significant effects reported |
| 25. Reliance on a single measurement | +3.3 to +10.4 | −2.4 to +0.6 |
| 26. Interarm variability | |3.3| to |6.32| | |2.7| to |5.06| |
| Observer-related | ||
| 27. Observer hearing deficit | −1.55 to −0.11 | +1.05 to +4.32 |
| 28. Korotkoff Phase IV (vs. V) for DBP | N/A | +12.5a |
| 29. Terminal digit preference for zero | 1–79% over-representation of terminal zero | 3–79% over-representation of terminal zero |
aOnly one study found a significant effect.
bNo study found a significant directional effect (although one found reduced variation in SBP).
Empirically-evaluated potential sources of inaccuracy that may be introduced at each stage in the process of measuring an adult’s resting blood pressure, and the reported direction of significant effects (note that numbers in parentheses correspond to the numbering of potential sources of inaccuracy in the ‘RESULTS’ section, Table 2 and the Supplementary Tables)
| Stage in the process of blood pressure measurement | Potential sources of inaccuracy introduced | Direction of significant effects | |
| SBP | DBP | ||
| Before measurement | Acute meal ingestion (1) | − | − |
| Acute alcohol use (2) | ± | ± | |
| Acute caffeine use (3) | + | + | |
| Acute nicotine use or exposure (4) | + | + | |
| Bladder distension (5) | + | + | |
| Cold exposure (6) | + | + | |
| Insufficient rest period (11) | + | + | |
| Selecting the device | Device model biasa (9) | ± | ± |
| Device calibration error (10) | ± | ± | |
| Positioning the patient | Standing body position (vs. sitting) (12) | ± | + |
| Supine body position (vs. sitting) (12) | ± | ± | |
| Legs crossed at knees (13) | + | + | |
| Unsupported back (14) | ns | + | |
| Unsupported arm (15) | + | + | |
| Arm lower than heart level (16) | + | + | |
| Attaching the device to the patient | Paretic arm (7) | + | + |
| Smaller cuff (vs. correct size) (17) | + | + | |
| Larger cuff (vs. correct size) (17) | − | − | |
| Cuff placed over clothing (18) | ns | ns | |
| Stethoscope under cuff (19) | + | − | |
| Taking the measurement | White-coat effect (8) | ± | ± |
| Talking during measurement (20) | + | + | |
| Use of stethoscope bell (vs. diaphragm) (21) | ± | − | |
| Excessive pressure on stethoscope head (22) | ns | − | |
| Fast cuff deflation rate (23) | − | + | |
| Observer hearing deficit (27) | − | + | |
| Korotkoff phase IV (vs. V) for DBP (28) | N/A | + | |
| Short interval between measurements (24) | ns | ns | |
| Interpreting the measurement | Reliance on a single measurement (25) | + | ± |
| Interarm variabilityb (26) | ± | ± | |
| Terminal digit preference for zero (29) | ± | ± | |
Symbols indicate whether significant increases (+), significant decreases (−) or both (±) were reported. Sources for which all reported directional effects were nonsignificant are marked ns.
aDirection depends on the device type and model (Table (Table22 and Supplementary Tables 9A–9E).
bDirection depends on which arm was selected for measurement (individuals differ in which arm will yield the higher values).
Reference and source
Kallioinen N, Hill A, Horswill MS, Ward HE, Watson MO. Sources of inaccuracy in the measurement of adult patients’ resting blood pressure in clinical settings: a systematic review. Journal of Hypertension. 2017;35(3):421-441. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5278896/