Direct Use of Clinical Tolerance Limits for Assessing the Degree of Agreement between Two Methods of Measuring Blood Pressure

Abstract

A large number of new methods of measuring blood pressure (BP) have recently emerged with advances in technology. Different methods of measuring BP generally provide varying readings compared with one another. Clinicians must decide how to respond to these variations and how to assess the degree of agreement. Clinical agreement between two quantitative measurements on a group of subjects is generally assessed with the Bland-Altman method. This method requires a comparison of Bland-Altman limits with the prespecified clinical tolerance limits. This review describes an alternative simple and robust method that directly uses clinical tolerance limits for assessing agreement without calculating Bland-Altman limits. The many advantages of this method are illustrated with the help of real-life examples of BP measurements.