Psychometric validation of the Rhinitis Control Assessment Test: a brief patient-completed instrument for evaluating rhinitis symptom control

Abstract

Allergic rhinitis is common, but a validated tool for comprehensive assessment of disease control is not available. To develop a simple patient-completed instrument (the Rhinitis Control Assessment Test [RCAT]) to help detect problems with control of rhinitis symptoms. During a visit to an allergy specialist, 410 patients with allergic rhinitis completed a Total Nasal Symptom Score (TNSS) assessment and the 26-item developmental RCAT. Physicians also completed a global assessment of rhinitis symptom control for each patient. Stepwise regression methods identified 6 items from the developmental RCAT (frequency of nasal congestion, sneezing, and watery eyes; sleep interference; activity avoidance; and self-assessed control) that were most predictive of the allergist's global rating of rhinitis symptom control. A summated rating scale from these 6 items showed good convergent validity (r > 0.70) with scale scores from the TNSS. The discriminant validity of the 6-item scale was demonstrated as mean RCAT scale scores differed significantly across groups of patients differing in physician-rated disease severity (F = 54.4), TNSS severity (F = 193.8), and physician-recommended change in therapy (F = 50.6) (P < .001 for all). The RCAT, a 6-item patient-completed instrument, has satisfactory psychometric properties and seems to be a valid tool for assessing control of allergic rhinitis. Further validation studies will provide confirmation.