Investors interested in Medical Services stocks are likely familiar with AMN Healthcare Services (AMN) and Doximity (DOCS). But which of these two stocks is more attractive to value investors? We'll need to take a closer look to find out.Everyone has their own methods for finding great value opportunities, but our model includes pairing an impressive grade in the Value category of our Style Scores system with a strong Zacks Rank. The proven Zacks Rank emphasizes companies with positive estimate revision trends, and our Style Scores highlight stocks with specific traits.Currently, AMN Healthcare Services has a Zacks Rank of #2 (Buy), while Doximity has a Zacks Rank of #3 (Hold). This means that AMN's earnings estimate revision activity has been more impressive, so investors should feel comfortable with its improving analyst outlook. But this is just one piece of the puzzle for value investors.Value investors also try to analyze a wide range of traditional figures and metrics to help determine whether a company is undervalued at its current share price levels.Our Value category grades stocks based on a number of key metrics, including the tried-and-true P/E ratio, the P/S ratio, earnings yield, and cash flow per share, as well as a variety of other fundamentals that value investors frequently use.AMN currently has a forward P/E ratio of 10.57, while DOCS has a forward P/E of 50.59. We also note that AMN has a PEG ratio of 3.17. This popular figure is similar to the widely-used P/E ratio, but the PEG ratio also considers a company's expected EPS growth rate. DOCS currently has a PEG ratio of 13.65.Another notable valuation metric for AMN is its P/B ratio of 4.67. The P/B ratio pits a stock's market value against its book value, which is defined as total assets minus total liabilities. For comparison, DOCS has a P/B of 7.61.These are just a few of the metrics contributing to AMN's Value grade of A and DOCS's Value grade of D.AMN sticks out from DOCS in both our Zacks Rank and Style Scores models, so value investors will likely feel that AMN is the better option right now. Zacks Names "Single Best Pick to Double" From thousands of stocks, 5 Zacks experts each have chosen their favorite to skyrocket +100% or more in months to come. From those 5, Director of Research Sheraz Mian hand-picks one to have the most explosive upside of all. It’s a little-known chemical company that’s up 65% over last year, yet still dirt cheap. With unrelenting demand, soaring 2022 earnings estimates, and $1.5 billion for repurchasing shares, retail investors could jump in at any time. This company could rival or surpass other recent Zacks’ Stocks Set to Double like Boston Beer Company which shot up +143.0% in little more than 9 months and NVIDIA which boomed +175.9% in one year.Free: See Our Top Stock and 4 Runners Up >>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 AMN Healthcare Services Inc (AMN): Free Stock Analysis Report Doximity, Inc. (DOCS): Free Stock Analysis ReportTo read this article on Zacks.com click here.Zacks Investment Research