RESUMEN
OBJECTIVE: To assess the effect of morphine equivalent dose-days (MED-D) on the total cost for acute low back pain (LBP) workers' compensation claims. METHODS: Simple random samples of 123 opioid and 141 nonopioid acute LBP claims were obtained. Opioid claims were divided into low, medium, and high subgroups for MED-D, MED, and prescription duration. Subgroup mean total costs were compared to the nonopioid group using multivariate regression analyses. RESULTS: MED-D and prescription duration were each, respectively, associated with significantly increased total costs at both medium and high levels. Increasing MED had a negative association with total cost, though stratification by duration abrogated this perceived trend. Interaction testing indicated MED and duration together better explained cost than MED alone. CONCLUSION: MED-D is a better predictor of total cost in acute LBP claims than MED alone.