Clinimetrics: Core Outcome Set for trials with Coronavirus disease 2019 (COVID-19-COS).

Abstract

The Core Outcome Set (COS) for trials in Coronavirus Disease 2019 (COVID-19-COS) aimed to establish a consistent and standardised list of outcomes to be measured and reported, as a minimum, in trials treating patients with COVID-19.1 The COVID-19-COS was developed according to the Core Outcome Measures in Effectiveness Trial (COMET) framework, using a series of online workshops involving adults who had experienced suspected or confirmed COVID-19, their family members, the general public and health professionals from 111 countries.1 The COVID-19-COS specifies mortality, respiratory failure, multiple organ failure, shortness of breath, and recovery as the most critically important outcomes for trials involving participants with COVID-19.2

Core outcome measures for the COVID-19-COS outcome domains were proposed,2 using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) framework to identify appropriate measures and their clinimetric properties. Mortality is measured, according to World Health Organization (WHO) recommendations, at hospital discharge or at 60 days.2 The outcome measure for respiratory failure is a modified version of the WHO clinical progression scale, with scores between 4 (hospitalised with no oxygen therapy) and 9 (extracorporeal membrane oxygenation) reflecting the increasing need for respiratory support.2 , 3 Validation of this scale is not yet available; however, it has already been used in COVID-19 trials.4 , 5

Multiple organ failure is measured using the Sequential Organ Failure Assessment (SOFA) score, which is commonly used in research and clinical practice. It has been validated for use in hospital and ICU settings and also provides prognostic information regarding survival.6 Shortness of breath is measured using the Modified Medical Research Council (MMRC) dyspnoea scale, with minor adaptations to the original wording and the addition of a recall period of 24 hours to capture daily fluctuations. The MMRC is a simple 5-point scale that has been extensively validated in patients with chronic respiratory disease.7 , 8 No existing outcome measure for recovery was identified, so a new COVID-19-COS recovery measure was proposed, consisting of a 5-point Likert scale with anchors ‘not recovered at all’ and ‘completely recovered’. No clinimetric data are available for this new recovery measure.2