By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) – The one thing that is constant in medicine is change and tried and true tools often can be replaced over time.

An example might be the Pap smear. Back in 2011 the HPV test was approved to be used in conjunction with Pap smears and recently the FDA has found it to be just as reliable on its own as a Pap smear is at screening for cervical cancer.

Of course a great deal of research is being done and a report in the Annals of Internal Medicine is just the latest.

The researchers studied more than 40,000 women who received both tests and they found that the HPV test alone would have been sufficient to catch cervical cancers early. It is clear that they will continue to look at pros and cons of each test and things may change.