CMS will toughen up scrutiny for diabetic test strips, oxygen, and wheelchairs. After being called out on artificially lowering the DME payment error rate, the Centers for Medicare & Medicaid Services has agreed to implement most of these recommendations from the HHS Office of Inspector General: 1. Require the Comprehensive Error Rate Testing (CERT) contractor to review all available durable medical equipment supplier documentation. 2. Require the CERT contractor to review all medical records (including, but not limited to, physicians' records) necessary to determine compliance with applicable requirements on medical necessity. These first two recommendations will cost an additional $1.25 to $2.5 million, a 10 to 20 percent increase over the current CERT budget, CMS notes in its response to the OIG report. "We acknowledge that expanding the review process may increase the cost of the CERT program and the time required to conduct reviews," the OIG says. "But, based on our findings, such an expansion is necessary to ensure an accurate measurement of DME payment errors." CMS began requiring the CERT contractor to look at physician medical records and not just certificates of medical necessity (CMNs) last year, CMS added. 3. Establish a written policy to address the appropriate use of clinical inference. Using clinical inference instead of documentation was the problem with many of AdvanceMed's missed calls, the OIG and its review contractor, KePRO, found. CMS already has written guidance on clinical inference in the Program Integrity Manual and has trained contractor staff on it, the agency maintains. CMS agrees with the recommendation. 4. Document oral guidance that conflicts with written policies, such as guidance on the need for proof-of-delivery documentation in making medical review determinations. "CMS agrees that guidance to the CERT contractor should be consistent with written policy and documented in the appropriate program and/or contract documents," the agency says. 5. Instruct its Medicare contractors to provide additional training to physicians that focuses on improving their medical record documentation to support ordered DME items. CMS already requires contractors to train providers on problems in the CERT report, it notes. 6. Require the CERT contractor to contact the beneficiaries named on high-risk claims, such as claims for power mobility devices, to help determine whether the beneficiaries received these items and the items were medically necessary. The agency will test the expanded requirements, including beneficiary interviews, for high-risk items -- diabetic test strips, oxygen and power mobility devices -- starting in 2009, it says.