TNF and rheumatoid arthritis: Examples of large-scale observational studies from this project are a study of biologics used in 42,638 RA patients with a history of malignancy (38) and another study to assess the risk of neuroinflammatory events in 25,796 RA patients, 8,586 PsA patients, and 9,527 AS patients treated with TNF-alpha inhibitors (39).