Healthcare providers who participate in more than one new payment model may face some confusion about the models’ results, an official with the Centers for Medicare & Medicaid Services acknowledged this week.

Speaking at the America’s Health Insurance Plans’ Medicare conference on Tuesday, CMS Deputy Administrator Patrick Conway, M.D., said the agency is aware that overlap is becoming more common as more payment models are introduced. CMS is working to make results of the models more easily attributable so that providers know which program generated savings.

“These models can and should work together,” Conway said.

CMS is also facing a challenge in how it assigns patients to the models, Bloomberg BNA reported. In some cases savings can be shared between two payment models. However, for beneficiaries assigned to full-risk models savings from those would “trump a bundled payment model,” Conway said.

“I worked in a health system with ACOs and bundles and it worked well,” he noted. “But every local market works in different ways.

CMS’ Center for Medicare & Medicaid Innovation currently lists 76 payment and service delivery models — models that have riled up lawmakers in recent weeks. In a letter to Conway and CMS Acting Administrator Andy Slavitt, House lawmakers urged the agency to stop making new payment models mandatory and instead focus on “prior testing on a smaller scale.”