The ReFlaP study aimed to establish cut-off values for commonly used composite scores and patient-reported outcomes (PROs) in psoriatic arthritis (PsA). These cut-offs correspond to different disease states - specifically remission and low disease activity - as well as to changes indicating disease flare, as defined from both patient and physician perspectives. A total of 466 patients with rheumatologist-confirmed PsA and a disease duration of more than two years were enrolled across 21 centres in 14 countries. Participants were assessed at baseline in 2017 and followed up between 1 and 6 months later.