Development and evaluation of an improved methodology for assessing adherence to evidence-based drug therapy guidelines using claims data.

Non-adherence to evidence-based pharmacotherapy is associated with increased morbidity and mortality. Claims data can be used to detect and intervene on such non-adherence, but existing claims-based approaches for measuring adherence to pharmacotherapy guidelines have significant limitations. In this manuscript, we describe a methodology for assessing adherence to pharmacotherapy guidelines that overcomes many of these limitations. To develop this methodology, we first reviewed the literature to identify prior work on potential strategies for overcoming these limitations. We then assembled a team of relevant domain experts to iteratively develop an improved methodology. This development process was informed by the use of the proposed methodology to assess adherence levels for 14 pharmacotherapy guidelines related to seven common diseases among approximately 36,000 Medicaid beneficiaries. Finally, we evaluated the ability of the methodology to overcome the targeted limitations. Based on this evaluation, we conclude that the proposed methodology overcomes many of the limitations associated with existing approaches.