Fig. 2From: Association between spinal manipulative therapy and lumbar spine reoperation after discectomy: a retrospective cohort studyPropensity score density graph. Propensity scores before (A) and after (B) matching. The orange line and fill represent the spinal manipulative therapy (SMT) cohort while the blue line and fill represent the usual care cohort. Following matching, the propensity score densities overlap suggesting adequate balance of covariatesBack to article page