The Medical group has plenty of great stocks, but investors should always be looking for companies that are outperforming their peers. Is UnitedHealth Group (UNH) one of those stocks right now? By taking a look at the stock's year-to-date performance in comparison to its Medical peers, we might be able to answer that question.UnitedHealth Group is a member of the Medical sector. This group includes 1050 individual stocks and currently holds a Zacks Sector Rank of #16. The Zacks Sector Rank considers 16 different groups, measuring the average Zacks Rank of the individual stocks within the sector to gauge the strength of each group.The Zacks Rank is a successful stock-picking model that emphasizes earnings estimates and estimate revisions. The system highlights a number of different stocks that could be poised to outperform the broader market over the next one to three months. UNH is currently sporting a Zacks Rank of #2 (Buy).The Zacks Consensus Estimate for UNH's full-year earnings has moved 0.93% higher within the past quarter. This is a sign of improving analyst sentiment and a positive earnings outlook trend.Based on the latest available data, UNH has gained about 19.68% so far this year. At the same time, Medical stocks have lost an average of 2.72%. As we can see, UnitedHealth Group is performing better than its sector in the calendar year.Breaking things down more, UNH is a member of the Medical - HMOs industry, which includes 10 individual companies and currently sits at #32 in the Zacks Industry Rank. On average, stocks in this group have gained 20.05% this year, meaning that UNH is slightly underperforming its industry in terms of year-to-date returns.Investors in the Medical sector will want to keep a close eye on UNH as it attempts to continue its solid performance. 5 Stocks Set to Double Each was hand-picked by a Zacks expert as the #1 favorite stock to gain +100% or more in 2021. Each comes from a different sector and has unique qualities and catalysts that could fuel exceptional growth. Most of the stocks in this report are flying under Wall Street radar, which provides a great opportunity to get in on the ground floor. Today, See These 5 Potential Home Runs >>Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report UnitedHealth Group Incorporated (UNH): Free Stock Analysis Report To read this article on Zacks.com click here.