1069. Psychometric Properties of the Symptoms of Infection with Coronavirus-19: A Patient-Reported Outcome Measure for COVID-19 Signs and Symptoms

Abstract Background The Symptoms of Infection with Coronavirus-19 (SIC), a patient reported outcome (PRO) measure, was developed to assess COVID-19 signs and symptoms. Qualitative cross-sectional studies demonstrated its content validity preliminary psychometric properties. This study provides additional evidence on the reliability, responsiveness, known-group validity, meaningful change thresholds SIC using methods aligned regulatory guidance best practices. Methods Data were from ENSEMBLE-2, multicenter, randomized, double-blind, placebo-controlled phase 3 trial efficacy safety Ad26.COV2.S for prevention SARS-CoV-2 infections in adults (aged 18+). used evaluate symptoms Patient Global Impression Severity (PGIS) as an anchor validation. Intra-class correlations (ICCs) Cronbach’s alphas computed test-retest reliability internal consistency, analyses variance (ANOVAs) performed SIC. Responsiveness evaluated PGIS variable 1- or 2-point improvement estimate Results 183 participants polymerase chain reaction (PCR) confirmed moderate severe/critical included (mean ± SD age: 51.5 14.8 y; female: 44%; White 65%). ICCs showed strong reliabilities most domains (.60 above). consistency had alpha > .70 all but one domain (Neurological). Statistically significant differences (p values < 0.05) different severity levels found (Sensory), supporting validity. All responsiveness based changes (improvement worsening) PGIS, ability detect Based mean estimated ranged -.36 -2.11. Conclusion These results, data build upon prior provide supportive Support: Janssen Vaccines & Prevention B.V. Disclosures Eric K. H. Chan, PhD, Services, LLC: Employee|Janssen Pharmaceuticals: Stocks/Bonds Jeffrey Stoddard, MD, Jerald Sadoff, BV: Employee Yan Liu, Ilse van Dromme, Eva G. Katz, MPH, RD, Yi-hsuan MS, Kelly McQuarrie, BSN, Stocks/Bonds.