Statistical sampling for overpayment estimation in future audits and investigations

The Delaware Division of Medicaid and Medical Assistance (DMMA) is now using statistical sampling to calculate the estimated overpayment in audits for a specific provider/supplier. The process requires a Statistically Valid Random Sample (SVRS), which is a random selection of sampling units (e.g., claims) from a population (i.e., universe). Medical records are requested from the provider/supplier for the sample items and reviewed by a nurse who determines whether the services should be paid or denied and the associated overpayment amount. The sample results are used to project (i.e., extrapolate) the overpayment to the universe and calculate the estimated overpayment. Educational materials on the use of the statistical sampling for overpayment estimation are available to the provider community through the provider portal.