Note: Steps 4-7 are specific to auscultation.

Supplemental Table S2.
Recommended Technique for Automated Office Blood Pressure (AOBP)
  1. Measurements should be taken with a validated sphygmomanometer known to be accurate.
  2. Choose a cuff with an appropriate bladder size matched to the size of the arm. Select the cuff size as recommended by its manufacturer.
  3. Place the cuff so that the lower edge is 3 cm above the elbow crease and the bladder is centered over the brachial artery. There is no rest period needed before measurement. The arm should be bare and supported with the BP cuff at heart level, as a lower position will result in an erroneously higher SBP and DBP. There should be no talking, and patients’ legs should not be crossed.
  4. When using automated office oscillometric devices, the patient should be seated in a quiet room (no specified period of rest). With the device set to take measures at 1- or 2-minute intervals. The first measurement is taken by a health professional to verify cuff position and validity of the measurement. The patient is left alone after the first measurement while the device automatically takes subsequent readings.
  5. Record the average BP as displayed on the electronic device as well as the arm used and whether the patient was supine, sitting or standing. Record the heart rate.
Recommended Technique for Office Blood Pressure Measurement (non-AOBP)
  1. Measurements should be taken with a sphygmomanometer known to be accurate. A validated electronic device should be used. If not available, a recently calibrated aneroid device can be used. Aneroid devices or mercury columns need to be clearly visible at eye level.
  2. Choose a cuff with an appropriate bladder size matched to the size of the arm. For measurements taken by auscultation, bladder width should be close to 40% of arm circumference and bladder length should cover 80 – 100% of arm circumference. When using an automated device, select the cuff size as recommended by its manufacturer.
  3. Place the cuff so that the lower edge is 3 cm above the elbow crease and the bladder is centered over the brachial artery. The patient should be resting comfortably for 5 minutes in the seated position with back support. The arm should be bare and supported with the BP cuff at heart level, as a lower position will result in an erroneously higher SBP and DBP. There should be no talking, and patients’ legs should not be crossed. The first reading should be discarded and the latter two averaged. BP should also be assessed after 2 minutes standing (with arm supported) and at times when patients report symptoms suggestive of postural hypotension. Supine BP measurements may also be helpful in the assessment of elderly and diabetic patients. When using automated office oscillometric devices such as the BpTRU (VSM MedTech Ltd, Vancouver, Canada), the patient should be seated in a quiet room (no specified period of rest). With the device set to take measures at 1- or 2-minute intervals, the first measurement is taken by a health professional to verify cuff position and validity of the measurement. The patient is left alone after the first measurement while the device automatically takes subsequent readings. The BpTRU automatically discards the first measure and averages the next 5 measures. For auscultation, at least three measurements should be taken in the same arm with the patient in the same position. The first reading should be discarded and the latter two averaged.
Steps 4-7 are specific to auscultation.
  1. Increase the pressure rapidly to 30 mmHg above the level at which the radial pulse is extinguished (to exclude the possibility of a systolic auscultatory gap).
  2. Place the bell or diaphragm of the stethoscope gently and steadily over the brachial artery.
  3. Open the control valve so that the rate of deflation of the cuff is approximately 2 mmHg per heart beat. A cuff deflation rate of 2 mmHg per beat is necessary for accurate systolic and diastolic estimation.
  4. Read the systolic level -the first appearance of a clear tapping sound (phase I Korotkoff) and the diastolic level- the point at which the sounds disappear (phase V Korotkoff). If Korotkoff sounds persist as the level approaches 0 mmHg, then the point of muffling of the sound is used (phase IV) to indicate the diastolic pressure. Leaving the cuff partially inflated for too long will fill the venous system and make the sounds difficult to hear. To avoid venous congestion, it is recommended that at least one minute should elapse between readings.
  5. Record the BP to the closest 2 mmHg on the manometer (or 1 mmHg on electronic devices) as well as the arm used and whether the patient was supine, sitting or standing. Avoid digit preference by not rounding up or down. Record the heart rate. The seated BP is used to determine and monitor treatment decisions. The standing BP is used to examine for postural hypotension, if present, which may modify the treatment.
  6. In the case of arrhythmia, additional readings with auscultation may be required to estimate the average systolic and diastolic pressure. Isolated extra beats should be ignored. Note the rhythm and pulse rate.
  7. BP should be taken in both arms on at least one visit and if one arm has a consistently higher pressure, that arm should be subsequently used for BP measurement and interpretation.
Recommended Technique for Home Blood Pressure Measurement
  1. Measurements should be taken with a validated electronic device.
  2. Choose a cuff with an appropriate bladder size matched to the size of the arm. Bladder width should be close to 40% of arm circumference and bladder length should cover 80 – 100% of arm circumference. Select the cuff size as recommended by its manufacturer.
  3. Cuff should be applied to the non-dominant arm unless the SBP difference between arms is >10 mmHg, in which case the arm with the highest value obtained should be used.
  4. The patient should be resting comfortably for 5 minutes in the seated position with back support.
  5. The arm should be bare and supported with the BP cuff at heart level.
  6. Measurement should be performed before breakfast and 2 hours after dinner, before taking medication.
  7. No caffeine or tobacco in the hour and no exercise 30 minutes preceding the measurement.
  8. Duplicate measurement should be done in the morning and in the evening for seven days (i.e., 28 measurements in total).
  9. Average the results excluding the first day’s readings.
Recommended Technique for Ambulatory Pressure Monitoring
  1. The appropriate sized cuff should be applied to the non-dominant arm unless the SBP difference between arms is >10 mm Hg, in which case the arm with the highest value obtained should be used.
  2. The device should be set to record for a duration of at least 24 hours with the measurement frequency set at 20-30 minute intervals during the day and 30-60 minutes at night.
  3. A patient-reported diary to define daytime (awake), night-time (sleep), activities, symptoms and medication administration is useful for study interpretation.
  4. Daytime and night-time should preferentially be defined using the patient’s diary. Alternatively, predefined thresholds can be used (e.g. 8 AM to 10 PM for awake and 10 PM and 8 AM for night-time).
  5. The ambulatory BP monitoring report should include all of the individual BP readings (both numerically and graphically), the percentage of successful readings, the averages for each time frame (daytime, night-time, 24 hours) and the “dipping” percentage (the percentage the average BP changed from daytime to night-time).
  6. Criteria for a successful ambulatory BP monitoring study are:
    1. At least 70% of the readings are successful, AND
    2. At least 20 daytime readings and 7 night-time readings are successful.

    Abbreviations: BP, blood pressure; DBP, diastolic BP; SBP, systolic BP. Unless otherwise mentioned, steps apply to measurement by auscultation and oscillometry using an upper arm cuff.