CRS-PRO: A new patient centered outcome measure for chronic rhinosinusitis
Published online: April 30, 2020
Patient reported outcome (PRO) measures quantify the subjective experience of chronic disease from the patient’s perspective and can serve as endpoints for clinical trials. Few PRO instruments for chronic rhinosinusitis (CRS) have been developed with documented input from patients with current CRS definitions, especially those with CRS with nasal polyps. Subsequently, none have been formally accepted by the Food and Drug Administration (FDA) as an endpoint for clinical trials. The Sino-nasal outcome test – 22 (SNOT-22) is the best validated patient reported outcome measure for CRS. However, its development process may preclude FDA acceptance as an endpoint for clinical trials due to its development prior to current definitions of CRS and subsequent modifications without documented patient input. In addition, some concepts in the SNOT-22 are disproportionately weighted (e.g. multiple questions related to sleep), mapped to several concepts (e.g. frustrated/restless/irritable), or are generally not reported at high burden by patients with CRS (e.g. sad, embarrassed, sneezing, dizziness). In an article recently published in The Journal of Allergy and Clinical Immunology: In Practice, Ghadersohi et. al. describe the development and validation of a new 12-item PRO measure that was developed using extensive input from patients with current disease definitions of CRS, including those with and without polyps (CRSwNP and CRSsNP).
The full development and initial validation of the CRS-PRO is described in two articles. The first article entitled: “Development and Preliminary Validation of a New Patient Reported Outcome Measure for Chronic Rhinosinusitis (CRS-PRO)” describes the use of several focus groups of CRS patients (CRS with and without polyps) to develop a 21-item CRS-PRO. These items were then administered to a separate cohort of 50 CRS patients with stable disease along with the SNOT-22 and several general quality of life measures, including the PROMIS and the EQ-5L, at an initial visit then approximately 1 week later. The reliability and validity of the CRS-PRO was demonstrated, meaning that the instrument captured the core concepts of CRS and produced stable results. Through careful assessment of individual item responses, the authors were able to further refine the instrument to 12 items using patient responses to help eliminate redundant or low impact items while maintaining key metrics of reliability.
In the second article entitled “Responsiveness and Convergent Validity of a New Patient Reported outcome measure for Chronic Rhinosinusitis (CRS-PRO).” Ghadersohi et al. studied a second cohort of 51 CRS patients that underwent appropriate medical therapy (typically nasal steroid sprays, with or without antibiotics or systemic steroids). Each patient was given the battery of PRO measures including the CRS-PRO, SNOT-22 and general quality of life measures. In addition, the patients also underwent a battery of objective testing including nasal endoscopy, computed tomography (CT) of the sinuses, smell testing and nasal inspiratory flow testing prior to, and 4-6 weeks after, initiating medical therapy.
The results of the study showed that the 12-item CRS-PRO was a responsive instrument and captured improvement quantitatively. Interestingly, the 12-item CRS-PRO showed moderate correlations with the captured objective measures derived from validated CT and endoscopic severity measures. The authors concluded that the newly developed and concise 12-item CRS-PRO possesses the favorable psychometric properties of the SNOT-22. Furthermore, since the CRS-PRO was developed with well-documented extensive input from patients with contemporary definitions of CRSsNP and CRSwNP, it is in concordance with FDA guidelines for PRO measures acceptable for use as endpoints in clinical trials.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.