The Affordable Care Act: how can we know whether the intended consequences are occurring and the unintended ones are being avoided?

When the Affordable Care Act (ACA) was signed into law on March 23, 2010, policymakers intended that it would improve access to care by lowering the uninsured rate, improve health care quality, and lower costs. Now, 4 years later, researchers and policymakers need to ask whether those intentions have been realized or whether the ACA has produced unintended consequences that affect patient care. This article raises the importance of assessing what changes in patient access and clinical care have occurred, points out how challenging those assessments may be to conduct, and concludes with a call to action about how those challenges might be addressed.