Fig. 4
From: A prospective observational study on trajectories and prognostic factors of mid back pain
Six-cluster solution. The trajectories describe rapidly improving pain, starting either from mild (Cluster C, green), moderate (Cluster D, light blue) or from severe pain (Cluster A, red; Cluster B, yellow) describe rapidly improving pain (‘marked decrease in pain intensity within one month’ [30]) followed by recovery/minor pain (Cluster A and C) or mild pain (Cluster B and D) [30] after one year with one cluster (Cluster D) showing some slight pain exacerbation at three months