The grades of five health care provider stocks are better this week, according to the Portfolio Grader database. Every one of these stocks has an “A” (“strong buy”) or “B” overall (“buy”) rating.

Cross Country Healthcare, Inc. (CCRN) ups its rating to a B (“buy”) this week after earning a C (“hold”) in the week before. Cross Country Healthcare provides healthcare staffing and outsourcing services to the healthcare market. In Portfolio Grader’s specific subcategories of Earnings Momentum, Earnings Surprise and Sales Growth, CCRN also gets A’s. Shares of the stock have been trading at an exceptionally rapid pace, up threefold from the week prior. For more information, get Portfolio Grader’s complete analysis of CCRN stock.

Triple-S Management Corporation Class B (GTS) shows solid improvement this week. The company’s rating rises from an A to a C. Triple-S Management is an independent licensee of the Blue Cross Blue Shield Association. Shares of the stock have been trading at an exceptionally rapid pace, up twofold from the week prior. For more information, get Portfolio Grader’s complete analysis of GTS stock.

This week, Fresenius Medical Care AG & Co. KGaA Sponsored ADR’s (FMS) ratings are up from a C last week to a B. Fresenius Medical Care offers kidney dialysis services and manufactures and distributes equipment and products used in the treatment of dialysis patients. Shares of the stock have been trading at an exceptionally rapid pace, up fourfold from the week prior. For more information, get Portfolio Grader’s complete analysis of FMS stock.

Bio-Reference Laboratories, Inc. (BRLI) is making headway this week, with the company’s rating improving to an A (“strong buy”) from a B (“buy”) last week. Bio-Reference provides laboratory testing services, primarily to customers in the greater New York metropolitan area. Shares of the stock have been trading at an exceptionally rapid pace, up 412.7% from the week prior. For more information, get Portfolio Grader’s complete analysis of BRLI stock.

DaVita HealthCare Partners Inc. (DVA) earns a B this week, jumping up from last week’s grade of C. DaVita operates kidney dialysis centers in the United States. For more information, get Portfolio Grader’s complete analysis of DVA stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.