This week, the ratings of three medical technology stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, MedAssets, Inc., (MDAS) falls to a D (“sell”), worse than last week’s grade of C (“hold”). MedAssets provides technology-enabled products and services for hospitals and health systems. In Portfolio Grader’s specific subcategories of Earnings Momentum and Earnings Revisions, MDAS also gets F’s. For more information, get Portfolio Grader’s complete analysis of MDAS stock.

Computer Programs and Systems, Inc. (CPSI) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). Computer Programs and Systems is a healthcare information technology company that designs, develops, markets, installs, and supports computerized information technology systems for small and midsize hospitals. The stock gets F’s in Earnings Revisions and Earnings Surprise. As of April 29, 2015, 15.5% of outstanding Computer Programs and Systems, Inc. shares were held short. To get an in-depth look at CPSI, get Portfolio Grader’s complete analysis of CPSI stock.

Slipping from a D to an F rating, athenahealth, Inc. (ATHN) takes a hit this week. Athenahealth provides ongoing billing, clinical-related, and other related services to medical group practices primarily in the United States. The stock also rates an F in Margin Growth. As of April 29, 2015, 28% of outstanding athenahealth, Inc. shares were held short. For more information, get Portfolio Grader’s complete analysis of ATHN 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.