A minimal common outcome measure set for COVID-19 clinical research

Clinical research is necessary for an effective response to an emerging infectious disease outbreak. However, research efforts are often hastily organised and done using various research tools, with the result that pooling data across studies is challenging. In response to the needs of the rapidly evolving COVID-19 outbreak, the Clinical Characterisation and Management Working Group of the WHO Research and Development Blueprint programme, the International Forum for Acute Care Trialists, and the International Severe Acute Respiratory and Emerging Infections Consortium have developed a minimum set of common outcome measures for studies of COVID-19. This set includes three elements: a measure of viral burden (quantitative PCR or cycle threshold), a measure of patient survival (mortality at hospital discharge or at 60 days), and a measure of patient progression through the health-care system by use of the WHO Clinical Progression Scale, which reflects patient trajectory and resource use over the course of clinical illness. We urge investigators to include these key data elements in ongoing and future studies to
expedite the pooling of data during this immediate threat, and to hone a tool for future needs.


John Marshall, on behalf of the WHO Working Group on the Clinical Characteristics of COVID-19 infection

International Forum for Acute Care Trialists (InFACT)
International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC)
Clinical Characterization Working Group, WHO


Journal: The Lancet Infectious Diseases
Pages: -
Year: 2020
DOI: https://doi.org/10.1016/S1473-3099(20)30483-7

Further Study Information

Current Stage: Completed
Date: February 2020
Funding source(s): Canadian Institutes of Health Research

Health Area

Disease Category: Infectious disease

Disease Name: Coronavirus

Target Population

Age Range: 0 - 120

Sex: Either

Nature of Intervention: Any

Stakeholders Involved

- Clinical experts
- Policy makers
- Researchers
- Trialists

Study Type

- COS for clinical trials or clinical research
- Recommendations for outcome measures (measurement/how)


- Semi structured discussion
- Trial registry

The working group met by videoconference and at a face to face meeting in Geneva to discuss multiple issues relevant to research into the clinical management of patients during the evolving outbreak. We agreed that a minimal but comprehensively collected core outcome set could facilitate study design and data sharing, and that this core set should include information on viral burden, early clinical course, and survival measured at a more distant time point.

We aggregated data from all registered trials or cohort studies targeting patients with Covid-19 infection registered on clinicaltrials.gov or on the Chinese Clinical Trials Registry - http://www.chictr.org.cn/abouten.aspx - to understand the spectrum of outcomes being collected.

We then developed a candidate core outcome set that was disseminated by email (MailChimp) to members of WHO expert panels and to members of clinical trials groups in critical care medicine and infectious diseases to seek their input on the proposed model – its elements and their calibration. Responses were compiled and incorporated into a revised core outcome set. Differences were resolved by majority vote of members of the Clinical Characterization group.