Although measurement of blood pressure in the clinic is said to be the cornerstone of decision making in hypertension, such measurements may be unrepresentative of a patient's true blood pressure because of random fluctuations and the white coat effect.1^–4 In addition, doctors rarely measure blood pressure according to recommended standards.4 Aimed at improving hypertension management, the 2003 US Joint National Committee recommends the use of self monitoring of blood pressure before considering the more expensive, but better validated ambulatory monitoring of blood pressure.2 Both the Joint National Committee and the 2003 guidelines from the European Society of Hypertension and the European Society of Cardiology suggest that self monitoring might also be used as an alternative to ambulatory monitoring for the diagnosis of white coat hypertension.1 2 The 2004 British Hypertension Society guidelines also acknowledge the increasing use of self monitoring in clinical practice and provide a threshold level for the diagnosis of hypertension (more than 135/85 mm Hg).3 In addition, two websites (www.bhssoc.org and www.dableducational.org) provide information on validated devices for self monitoring.

Cross sectional data and one outcome …