Fear Avoidance Predicts Persistent Pain in Young Adults With Low Back Pain: A Prospective Study.

Objectives: To (1) quantify relationships between low back pain (LBP) symptoms, physical activity, and psychosocial characteristics in young adults and (2) identify subclasses of young adults with distinct pain trajectories.

Design: Prospective cohort study with 12-month follow-up.

Methods: One hundred twenty adults (mean ± SD age, 20.