Characterization of active joint count trajectories in juvenile idiopathic arthritis

Methods A retrospective cohort study at two Canadian centres was performed. The longitudinal trajectories of AJC were described using latent growth curve modeling (GCM). Latent GCM is a novel technique that aims to classify individuals into statistically distinct groups based on individual response patterns so that individuals within a group are more similar than individuals between groups. The trajectory classes are each defined by a longitudinal growth curve. The association of baseline characteristics stratified by trajectory group was examined by univariate methods.