Table 1 Major societal recommendations regarding laboratory testing for risk stratification and triage

Centers for Disease Control and Prevention (CDC) guidelines [6]

Mentions lack of prospective data demonstrating laboratory testing in risk stratification of patients who are asymptomatic or with mild infection. Mentions that there is insufficient data to recommend for or against using laboratory values to guide management.

International Society for Thrombosis AND Haemostasis’s interim guidance (ISTH-IG) [7]

Recommends obtaining D-dimer, PTT, platelet count, and fibrinogen levels for all patients who present with COVID-19 as the measurements may be helpful for risk stratification (D-dimer markedly raised three- to fourfold, prothrombin time prolonged, platelet count < 100 × 10⁹, and fibrinogen < 2.0 g/L) of patients who may need close monitoring and admission to hospital. Monitoring of parameters after admission may be helpful as more aggressive critical care treatment is warranted and experimental therapies should be considered if parameters worsen.

Anticoagulation Forum (ACF) [12]

Not mentioned

American Society of Hematology (ASH) [8, 9]

Recommends monitoring D-dimer, PTT, platelet count, and fibrinogen. Mentions that worsening of these parameters may predict more aggressive critical care and experimental therapies might be considered.

American College of Chest Physicians (ACCP) [10]

Not mentioned

Scientific and Standardization Committee of ISTH (SCC-ISTH) [11]

States further study is required. Acknowledges that use of very elevated D-dimer (> 6 times upper limit of normal) is a consistent predictor of thrombotic events and poor overall prognosis in this population.

American College of Cardiology (ACC) [13]

Similar to other acutely ill medical patients without COVID-19. Regular monitoring of platelet count, PT, D-dimer, and fibrinogen is important to diagnose worsening coagulopathy. Mentions that the treatment of underlying conditions of DIC and bacterial superinfections is important.