1. Blood pressure measurement by mercury sphygmomanometer and other auscultation based devices Background information

2. Based on EHES Manual, Part B. Fieldwork Procedures, 2nd edition, 2016
Available at:
These slides can be used freely, translated and adapted to national use (e.g. concerning the equipment). However, it is important to keep in mind that no changes should be made to the measurement techniques, which need to be standardized.

3. Hypertension as a cardiovascular risk factor

4. What is blood pressure?
Systolic blood pressure (higher value), represents the pressure while the heart contracts to pump blood to the body
First appearance of a clear repetitive sounds (Phase I)
Diastolic blood pressure (lower value), represents the pressure when the heart relaxes between beats
Disappearance of the repetitive sounds (Phase V)

5. Risk factors of elevated blood pressure
Salt intake
Obesity
Smoking
Alcohol use
Sedentary lifestyle
Fat contents of the food

6. Factors affecting blood pressure levels
Measurement environment
Noise, temperature
Factors related to the participant
Factors related to the measurer
Measurement device
Cuff size
Side of the stethoscope
Factors related to the measurement procedure

7. Factors related to the participant
Emotions – white coat hypertension
Activities before measurement
Physical exercise
Eating
Smoking
Use of caffeine containing drinks
Alcohol use
Full bladder
Pain
Daily variation (time of the day, weekday)
Medication

8. Average magnitude of the participant effects
Systolic bp (mmHg)
Diastolic bp (mmHg)
Full bladder
 mmHg, even up to 50 mmHg if bladder uncomfortably distended
 10 mmHg, even up to 40 mmHg if bladder uncomfortably distended
Physical exercise before measurement
 mmHg
 7-8 mmHg
Heavy meal before measurement
 20 mmHg
Smoking before measurement
 mmHg
 8 mmHg
Tolonen H, Koponen P, Naska A et al. BMC Med Research Methodology 2015; 15:33. doi: /s

9. Factors related to the measurer
Systematic error that leads to both intra-observer and inter-observer error
E.g. measurer ignoring the standard technique
Terminal digit preference
Measurer rounding the pressure reading to a digit of his or her choosing, most often to zero
Measurer prejudice or bias
Measurer adjusts the pressure to meet his or her preconceived notion of what the pressure should be
Rose G et al. Lancet 1965; 1: 673-4

10. Average magnitude of device effects
Systolic bp (mmHg)
Diastolic bp (mmHg)
Diaphragm of the stethoscope instead of bell
 2 mmHg
 0-2 mmHg
Cuff too small
 3-12 mmHg
 2-8 mmHg
Cuff too large
 mmHg
Tolonen H, Koponen P, Naska A et al. BMC Med Research Methodology 2015; 15:33. doi: /s

11. Factors related to the measurement procedure
Resting time and activities before the measurement
Participant’s posture during the measurement
Sitting position
Support of the back and feet
Support and level of the arm used for the measurement
Possibility to see the device (follow the mercury bar movement)
Left vs. right arm
Talking or moving during the measurement
Placing the cuff
Upper arm vs. crook (bend) of the arm
Bare skin vs. over clothing
Side of stethoscope (bell or diaphragm)

12. Average magnitude of the effects of the measurement protocol (1/2)
Systolic bp (mmHg)
Diastolic bp (mmHg)
Not resting 3 to 5 minutes before measurement
 mmHg
 14 mmHg
Supine posture instead of sitting posture
 3-10 mmHg
 1-5 mmHg
Legs crossed
 5-8 mmHg
 3-5 mmHg
Back / feet unsupported
 5-15 mmHg
 6 mmHg
Left arm instead of right arm
 1-3 mmHg
 1 mmHg
Tolonen H, Koponen P, Naska A et al. BMC Med Research Methodology 2015; 15:33. doi: /s

13. Average magnitude of the effects of the measurement protocol (2/2)
Systolic bp (mmHg)
Diastolic bp (mmHg)
Arm unsupported during the measurement
 1-7 mmHg
 5-11 mmHg
Arm below heart level
 10 mmHg
Participant talks during the measurement
 mmHg
 6-10 mmHg
Cuff over clothing
 5 mmHg
Not reported
Tolonen H, Koponen P, Naska A et al. BMC Med Research Methodology 2015; 15:33. doi: /s

14. Acknowledgements
Slides prepared by: Hanna Tolonen and Päivikki Koponen Experiences and feedback from the EHES network have been utilized in the preparation of these slides Funding: Preparation of the slides is part of the activities of the EHES Coordinating Centre which has received funding from the EC/DG SANTÉ in through SANCO/2008/C2/02-SI EHES and Grand Agreement number , and in through Grand Agreement number /BRIDGE Health

15. Disclaimer
The views expressed here are those of the authors and they do not represent the Commission’s official position.