The home measurement device should be validated before use and at regular intervals during use. 4. Home BP should be monitored under the following conditions: The morning measurement should be made within 1 h after waking, after micturition, sitting after 1 to 2 min of rest, before drug ingestion, and before breakfast. The evening measurement should be made just before going to bed, sitting after 1 to 2 min of rest. 5. Home BP should be measured at least once in the morning and once in the evening. 6. All home BP measurements should be documented without selection, together with the date, time, and pulse rate. Use of devices with a printer or an integrated circuit memory is useful to avoid selection bias. 7. The home BP in the morning and evening should be averaged separately for a certain period. The first measurement on each occasion should be used for totaling. 8. Home BP values averaged for a certain period Z135/80 mm Hg indicate hypertension and Z135/85 mm Hg, definite hypertension. Normotension is defined as less an average BP o125/80 mm Hg and definite normotension as o125/75 mm Hg. American Society of ABPM: Ambulatory BP monitors measure BP by means of auscultatory or oscillometric methods. Auscultatory monitors use a microphone on the bladder cuff to detect the Korotkoff sounds. The advantage of this technique is that arm movement does not interfere with the recording; however, these monitors are sensitive to background noise. Oscillometric monitors sense arterial pressure vibrations and calculate systolic and diastolic values using an algorithmic approach. They are unaffected by background noise, but arm movement can cause errant readings. Both types of monitors are validated by the British Hypertension Society and the Association for the Advancement of Medical Instrumentation. 