Validation of Patient-Reported Outcomes for Clinical Trials in Allergic Rhinitis: A Systematic Review

Although regulatory authorities have recently recommended the use of a combined symptom-medication score as a primary efficacy end point, none has been psychometrically validated. Here, we sought to determine to what extent allergic rhinitis (AR)-related patient-reported outcomes (symptom scores, medication scores, disease control scores, and satisfaction or quality-of-life scales) have been assessed for construct, content, and/or criterion validity, reliability, responsiveness, and the minimal clinically important difference. We searched the PubMed database from January 1997 to June 2018 with logical combinations of key words related to validation, AR, and patient-rated outcomes and scales. From a total of 1705 potentially relevant publications, 55 were reviewed. Despite the current emphasis on a combined symptom-medication score for evaluating the efficacy of allergen immunotherapy in AR, symptom scores have not been extensively validated, and we did not find any publications describing the validation of a medication score. Disease control scales (mainly the Rhinitis Control Assessment Test, the Control of Allergic Rhinitis and Asthma Test, and the Allergic Rhinitis Control Test) and health-related quality-of-life scales (mainly the Rhinoconjunctivitis Quality of Life Questionnaire [RQLQ] and the mini-RQLQ) have been extensively validated in AR but have some practical disadvantages as primary efficacy criteria in clinical trials.