A Data Driven Policy to Minimize the Tuberculosis Testing Cost Among Healthcare Workers

Abstract Background The Centers for Disease Control and Prevention mandates that healthcare employees at high risk exposure to Tuberculosis (TB) undergo annual testing. Currently in the US, two methods of TB testing are commonly used: a two-step skin test or a whole-blood test. Each testing method has unique costs and considerations. Healthcare leadership’s test selection must not only account for direct cost such as material, procedure and resources, but also indirect costs such as employee workplace absence. Our purpose was to build a mathematical model to investigate the value loss perspective of these testing methods and assist leadership in their decision-making. Methods This model is based on an Upstate South Carolina healthcare employer’s costs affecting over 18,000 employees on 6 campuses. A process flow map identified the variations in TB testing methods that incorporated the varied material and procedural costs based on the Mantoux two-step tuberculin skin test (TST) and the Interferon-Gamma Release Assay test (IGRA). In addition to these direct costs, the subject’s time requirements involved with each test for 4 employee types and 6 travel-to-testing-site times were calculated. Results Regardless of direct cost variations, a switching point between testing procedures that minimized total system costs was most influenced by employee salary. In this model, an employee who is paid more than $48/hour should undergo IGRA blood testing irrespective of the travel time. As employee pay rate decreases to $30/hour, TST testing becomes more economical. Assuming an equal number of at-risk employees in each wage and travel category, switching from the current policy of 95% TST testing to integrated TST/IGRA testing would reduce TB compliance cost by 28%. Conclusions Mathematical modeling can assist healthcare system decision-makers in understanding the implications of employee TB compliance testing. This model distills the known direct costs of TST compared to IGRA testing and value loss perspectives of employee time into a definable switching point. Although actual costs and potential dollars saved depends on TB testing compliance rules and regulation, it appears that a mixed model of TB testing may be the most cost-effective approach for a large health care employer with multiple campuses.