Path diagram of the mediation model for pain catastrophizing on race and baseline pain intensity. Covariates in the model include age, sex, body mass index (BMI), living situation, comorbid anxiety, and comorbid hypertension. Path a represents the unstandardized path coefficient of pain catastrophizing regressed on race adjusted for covariates. Path b represents the unstandardized path coefficient of pain intensity regressed on pain catastrophizing, adjusted for covariates. Path c represents the unstandardized path coefficient of race regressed on pain intensity, adjusted for covariates without controlling for pain catastrophizing. Path c’ represents the unstandardized path coefficient of race regressed on pain intensity, after controlling for covariates and pain catastrophizing. The total indirect effect (c – c’) indicates the difference between the effect of race on pain intensity when pain catastrophizing is controlled versus when it is not. Pain catastrophizing is supported as a mediator because the 95% CI for the total indirect effect does not include zero. M = mediator; X = independent variable; Y = dependent variable.