Count-valued time series models for COVID-19 daily death dynamics.

We propose a generalized non-linear state-space model for count-valued time series of COVID-19 fatalities. To capture the dynamic changes in daily COVID-19 death counts, we specify a latent state process that involves second-order differencing and an AR(1)-ARCH(1) model. These modelling choices are motivated by the application and validated by model assessment.

Persistence with anti-tumor necrosis factor therapies in patients with rheumatoid arthritis: observations from the RADIUS registry.

Objective: To evaluate persistence with anti-tumor necrosis factor (TNF) therapy and predictors of discontinuation in patients with rheumatoid arthritis (RA).

Methods: This retrospective analysis used data from RADIUS 1, a 5-year observational registry of patients with RA, to determine time to first- and second-course discontinuation of etanercept, infliximab, and adalimumab. First-course therapy was defined as first exposure to anti-TNF therapy, and second-course therapy was defined as exposure to anti-TNF therapy after the first discontinuation.

Rheumatoid arthritis disease-modifying antirheumatic drug intervention and utilization study: safety and etanercept utilization analyses from the RADIUS 1 and RADIUS 2 registries.

Objective: to report the rates of serious adverse events (SAE), serious infectious events (SIE), and events of medical interest (EMI) in patients receiving etanercept; to identify the risk factors for SAE, SIE, and EMI; and to report time to switching from etanercept therapy, reasons for switching, and time to restarting treatment with etanercept in patients with rheumatoid arthritis (RA) in US clinical practice.

Methods: adults ≥ 18 years of age who fulfilled the 1987 American Rheumatism Association criteria for RA were eligible for enrollment in 2 prospective, 5-year, multicenter, observational registries. RADIUS 1 (Rheumatoid Arthritis DMARD Intervention and Utilization Study) enrolled patients with RA who required a change in treatment [either an addition or a switch of a biologic or nonbiologic disease-modifying antirheumatic drug (DMARD)].

Real-world utilization of DMARDs and biologics in rheumatoid arthritis: the RADIUS (Rheumatoid Arthritis Disease-Modifying Anti-Rheumatic Drug Intervention and Utilization Study) study.

Objective: Rheumatoid Arthritis (RA) Disease-Modifying Anti-Rheumatic Drug (DMARD) Intervention and Utilization Study (RADIUS) is a unique, real-world, prospective, 5-year, observational study of over 10 000 patients with RA. RADIUS provides a snapshot of use patterns, effectiveness, and safety of DMARDs, biologics, and combination therapies used to manage RA in clinical practice.

Research Design And Methods: Patients with RA requiring a new DMARD or biologic (addition or switch) were eligible for the RADIUS study.