Validation of Rules of Two™ as a Paradigm for Assessing Asthma Control

Abstract

Assessing asthma control at each patient encounter is an essential task to determine pharmacologic requirements. Rules of Two (Ro2) was created from the original 1991 National Asthma Education Program guidelines to determine the need for controller therapy. This study determined the degree of agreement between Ro2 and the Expert Panel Report (EPR-3) definition of “in control” asthma and compared that value with the Asthma Control Test (ACT) in a group of asthmatics for the purpose of validating this tool. Patients with documented asthma were randomized to complete Ro2 or ACT prior to being assessed for asthma control by certified asthma educators using an EPR-3 template. Assessments occurred in either a specialty asthma clinic or at a local health fair. Patients were also queried for their personal assessment of asthma control. The primary statistical methodology employed was the degree of agreement (kappa) between each survey tool and the EPR-3 template. Of 150 patients, 72% did not have their asthma in control, based on the EPR-3 template. Ro2 identified 58% of patients not in control of their asthma, whereas ACT identified 36%, with kappa scores of 0.41 for Ro2 and 0.37 for ACT compared with the EPR-3 template. These were not significantly different. Of the 150 patients, 75% considered their asthma in control based on self-assessments, with a kappa of 0.23. In 14 of 73 ACT questionnaires, scores were not added or were misadded. Eliminating evaluation of static lung function significantly improved both kappa scores of Ro2 and ACT. In conclusion, Ro2 identifies patients with uncontrolled asthma as well as ACT and may be useful to the primary assessing clinician in determining asthma control.