Many health care stocks have been pummeled during the last few months. With such deep drops in prices, short-squeeze opportunities abound.

A short squeeze takes place when a stock's short-sellers cover their positions quickly when good news boosts the price of the stock. This short-covering often drives the stock price even higher. The metric for measuring short-squeeze plays is the short ratio, which represents the number of days it would take a stock's short-sellers to cover their position based on the stock's recent average daily volume.

Stockpickr has compiled a list of health care stocks with the highest short ratios, most of which have P/E ratios of less than 26 and PEG ratios of less than 1.8. They all have market caps of more than $500 million.

One health care stock with a high short ratio is HealthSouth (HLS), an operator of inpatient rehabilitation hospitals and long-term acute care hospitals. The stock has a short ratio of 35. The company just announced that it sold 8.8 million shares of common stock to JPMorgan Securities for approximately $150 million. Proceeds will be used for debt reduction and acquisitions. The stock has a forward P/E of 28 and a PEG of 3.88.

HealthSouth is owned by Highfields Capital Management, a Boston-based hedge fund with $11 billion under management. Highfields was founded in 1998 by Jonathon S. Jacobson and Richard L. Grubman. It also owns Clear Channel Communications (CCU), which has a 2.6 short ratio; Qualcomm (QCOM), with a 1.1 short ratio; and PNC Financial Services Group (PNC), with a 2.3 ratio.

Another heavily shorted health care stock is National Healthcare (NHC), which has a short ratio of 27.4. This operator of long-term health care centers reported a 16.1% increase in net income and a 14.3% increase in its dividend. The stock has a P/E of 14 and pays a yield of 2.2%.

National Healthcare shows up in a Stockpickr portfolio called Long Term Care Stocks, which contains stocks of companies in the business of long-term healthcare, which would benefit from the increasing number of senior citizens. The portfolio also includes Sun Healthcare Group (SUNH), with a 12.7 short ration; Kindred Healthcare (KND), with a 6.7 ratio; and Skilled Healthcare Group (SKH), with a 16.5 ratio.

Psychiatric Solutions (PSYS) is another company with a high short ratio, at 27.3. This in-patient behavioral health care company reported that its quarterly profit increased by 41 % and that revenue went up by 33% year over year. The stock has a P/E of 26 and a PEG of 0.8.

Psychiatric is owned by Angelo Gordon, an investment advisor founded in 1988, with $1 billion under management. Its goal is to generate absolute returns with low volatility by exploiting inefficiencies. It also likes Navteq (NVT), with a 3.4 ratio; Puget Energy (PSD), with a 5.5 ratio; and BCE (BCE), with a 1.5 ratio.

To see the rest of the health care stocks with high short ratios, check out the Health Care Short-Squeeze Plays portfolio at Stockpickr.com.