UnitedHealth Group (UNH) is one of the stocks most watched by Zacks.com visitors lately. So, it might be a good idea to review some of the factors that might affect the near-term performance of the stock. Over the past month, shares of this largest U.S. health insurer have returned -3.6%, compared to the Zacks S&P 500 composite's +5.1% change. During this period, the Zacks Medical - HMOs industry, which UnitedHealth falls in, has lost 3%. The key question now is: What could be the stock's future direction? ...