Comparison of open-source tariff method to IHME tariff method. The IHME random forest was tested on a set of IHME hospital-based data, both with and without health care experience (HCE) variables. The ORF was tested on a subset of the full IHME data, containing some, but not all, HCE variables. The OTM performed almost exactly as the similar IHME method on the full hospital-based dataset without HCE variables (for the top cause), but less well than the same IHME analysis with HCE variables. Note that results for the full IHME dataset without HCE were only available for the top assigned cause . HCE, health care experience; IHME, Institute for Health Metrics and Evaluation; OTM, open-source tariff method.