The RECoVERED Study is a prospective cohort study based in Amsterdam, the Netherlands. 342 Participants aged ≥18 years were enrolled between 11 May 2020 and 1 May 2021, following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) diagnosis via the local public health service and from hospitals. Standardized symptom questionnaires were completed at enrollment, 1 week and month later, and monthly thereafter. Clinical severity was defined according to World Health Organization (WHO) criteria.
Also pulmonary function was measured. At 28 days, six months, and twelve months after enrolment participants underwent standard pulmonary function testing (PFT). The following lung function parameters were measured: forced vital capacity (FVC), forced expiratory volume in one second (FEV1), vital capacity (VC), and alveolar volume (VA). In addition, pulmonary diffusion capacity for carbon dioxide (DLCO) was measured as an absolute value. Before each PFT, haemoglobin was measured and used in the measurement of DLCO. Reference values from the Global Lung Function Initiative (GLI) Equations and ERS were used for the spirometric and diffusion capacity parameters.
Health-Related Quality of Life was assessed with the Medical Outcomes Study Short Form 36-item health survey (SF-36).