Evaluation of Changes in Skin and Joint Outcomes and Associated Treatment Changes in Psoriatic Arthritis (PsA): Experience From the Corrona PsA/SpA Registry.

Objective: To characterize skin severity and joint activity outcomes and associated treatment changes in patients with psoriatic arthritis (PsA) through 12 months of follow-up after enrollment in the Corrona Psoriatic Arthritis/Spondyloarthritis (PsA/SpA) Registry.

Methods: Patients ≥ 18 years of age with a diagnosis of PsA and a history of psoriasis between March 21, 2013, and September 30, 2016, were enrolled (n = 647). Demographics, clinical features, and treatment characteristics were collected and stratified by skin severity and joint activity.

Understanding the association between skin involvement and joint activity in patients with psoriatic arthritis: experience from the Corrona Registry.

Objective: To compare the characteristics of patients with psoriatic arthritis among patient groups stratified by degree of skin and joint involvement, and to evaluate the relationship between skin severity and joint activity.

Methods: Body surface area (BSA) and Clinical Disease Activity Index (CDAI) at enrolment were analysed. Patient characteristics were stratified by skin severity and joint activity.

Crossover design and its application in late-phase diabetes studies.

Crossover design has been widely used in late-phase clinical studies, as well as in pharmacokinetic and pharmacodynamic, bioequivalence, and medical device studies; however, its interpretability and applicability continue to be debated. Herein we provide discussions around a crossover design's scientific benefit, applicability, and how it can be implemented in late-phase diabetes studies by properly handling key issues: carryover effect, washout period, and baseline selection. Specifically, detailed considerations are provided about the validity and situations of having appropriate length of study duration to deal with carryover effects so that a washout period may not be needed.