In this video, health-care analyst David Williamson discusses manged-care company Aetna's first-quarter results. Although the earnings have been kind to insurers, what sets Aetna apart is that it raised its guidance for the year, unlike UnitedHealth Group, which talked down the top end of its 2013 range and wouldn't touch 2014 in recent comments. 

Watch and find out why there may be even more upside in Aetna's shares in the short term and what threats are looming for insurance investors in 2014.

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

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