The OIG has issued a report entitled “MACs Continue to Use Different Methods to Determine Drug Coverage,” which reviews how Medicare Administrative Contractors (MACs) make Medicare Part B drug coverage determinations and ensure that claims are paid according to these determinations. Based on the results of a survey of MACs regarding 2012 Part B drug coverage polices, the OIG concludes that varying MAC methodologies may “contribute to inconsistencies in drug coverage across States” (e.g., different covered diagnosis codes). The OIG also pointed out that MACs experienced “difficulties interpreting CMS policy manuals and remaining up to date with sources for covered uses.” In addition, the MACs varied in the extent to which they implemented payment controls. The OIG recommends that CMS assign a single entity to assist MACs with making coverage determinations. CMS disagreed with this recommendation, stating that it would not capture regional differences that are fundamental to local coverage policy. In addition, the OIG called on CMS to evaluate the cost-effectiveness of implementing edits and conducting medical reviews to check the coverage of diagnosis codes on drug claims; CMS concurred and stated that CMS will conduct a study in 2017 to determine if increased monitoring of Part B drug claims results in fewer improper payments.