Cost-benefit of low back pain intervention using a classification test

A small percentage of workers' compensation low back pain (LBP) claimants experience a long duration disability and account for the large majority of compensation costs. Using classification-style evaluations administered early in the time course of the disability, previous studies have attempted to predict a claimant's disability duration as long vs. short. Presumably, early identification of long duration disability claimants would allow application of directed/targeted intervention, leading to a decrease in subsequent disability duration and cost. This paper presents a simple mathematical model of the cost-benefit expected from this type of intervention. The mathematical model leads to a cost-benefit equation with eight free parameters. Techniques for eliminating/estimating four of these parameters, combined with a technique for visualizing the remaining four parameters, allow a cost-benefit surface to be graphed with a three-dimensional plot. This model should be useful in quantifying the expected cost savings due to early intervention of targeted LBP cases.