Blood pressure readings tend to vary between measurements. A high or low blood pressure measured on a single occasion can be misleading and may not be representative of a patient’s “true” blood pressure. Clinical decisions should not be made on casual, isolated home measurements. Instead, the American Heart Association recommends that home blood pressure monitoring be based on 2 measurements taken at least one minute apart in the morning and evening optimally for 7 days (28 readings total) with a minimum of 3 days (12 readings total). The average of all blood pressure readings during this period should be calculated to provide an accurate assessment of blood pressure.