With more than 500 home-health testing kits on the market, you can now test yourself for everything from allergy sensitivities to cholesterol. The question is, would you skip going to the doctor if you could take a home-health test instead?

"In a recent survey fully half of the people said they would do the test. There are all kinds of tests out there now. Everything from allergies, to thyroid, to menopause. Good housekeeping decided to take a look at them and see if they were a good idea," said Toni Hope, health editor, Good Housekeeping.

Home menopause kits claim that a simple urine test can help determine whether a woman’s period changes are caused by menopause. "The problem with these tests is that the levels of FSH which are measured vary tremendously in a normal cycle. So if you don't measure them exactly at the right time, it may give you an answer which suggests that you're in menopause when you're not," said Dr. Michele Warren of Columbia University Medical Center.

And can a home allergy test tell you what you’re allergic to? Perhaps, says Dr. Clifford Bassett, vice chair, American Academy of Allergy, Asthma and Immunology. But if you need a more thorough test, see a doctor.

"Sometimes these home allergy tests kits may test for a variety of common allergens. Cow's milk, egg and wheat. That's all they test for. In the office, we want to focus on the most important allergens that affect an individual: the type of pollen, the type of food that may be causing an allergic reaction," Bassett explained.

Good Housekeeping had volunteers test their cholesterol using home kits, then compared results from a professional lab. "We found that the scores from CholesTrak came closest to the ones from the professional lab, but that test just gives you total cholesterol, not the breakdown of other kinds that you would need to really assess your risk for heart disease," said Hope.

Sales of home health kits now bring in nearly $3 billion a year. Good Housekeeping recommends if you do decide to play doctor at home, discuss the test results with your physician.

To learn more, check out the May issue of Good Housekeeping or visit www.goodhousekeeping.com.