Both WellPoint and UnitedHealth Group reported strong earnings that beat Wall Street expectations, but both are cautious heading into the Affordable Care Act's full implementation in 2014. Increased membership and declining medical costs saw full-year earnings guidance improve, powering both stocks higher. 

However, on their respective conference calls it wasn't just positive earnings surprises and guidance raises. Management has distinct concerns over the impact that decisions coming from Washington, D.C., will have on their business. Specifically cuts to the Medicare Advantage program weighed heavily, but both companies see opportunity in Obamacare as well.

In this video, health-care analyst David Williamson discusses the quarterly highlights, key takeaways from each company's conference call, and whether investors should be optimistic about their company's performance for this year and next.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid.

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