This week, four health care provider stocks are improving their overall rating on Portfolio Grader. Each of these rates an “A” (“strong buy”) or “B” overall (“buy”).

This week, Magellan Health, Inc. (MGLN) is showing significant improvement as the company’s rating hops from a C (“hold”) to a B (“buy”). Magellan Health Services coordinates and manages the delivery of behavioral healthcare treatment services. In Portfolio Grader’s specific subcategories of Earnings Surprise and Cash Flow, MGLN also gets A’s. 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 MGLN stock.

Amedisys, Inc. (AMED) gets a higher grade this week, advancing from a C last week to a B. Amedisys provides home health care and hospice services in the United States. For more information, get Portfolio Grader’s complete analysis of AMED stock.

This week, Concord Medical Services Holding Ltd. ADR (CCM) is making solid headway. The company’s rating improves to an A (“strong buy”) from last week’s B (“buy”) rating. Concord Medical Services operates a network of radiotherapy and diagnostic imaging centers in the People’’s Republic of China. For more information, get Portfolio Grader’s complete analysis of CCM stock.

Cardinal Health, Inc.’s (CAH) ratings are looking better this week, moving up to an A from last week’s B. Cardinal Health provides products and services related to the safety and productivity of healthcare. Shares of the stock have been changing hands at an unusually rapid pace, twice the rate of the week prior. For more information, get Portfolio Grader’s complete analysis of CAH 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.