According to estimates, one-third of all money spent on US health care is devoted to unnecessary tests and procedures. In a proactive effort to help stem healthcare spending, nine medical associations have joined a campaign called Choosing Wisely, to educate doctors and patients to use more caution regarding certain procedures.

"More isn't better," is the conclusion of the specialty doctors leading the campaign.

The medical groups have published their top 5 lists of tests, treatments, or services that are unnecessary or at least should include a thorough conversation between patients and their doctors regarding the benefits and risks before undertaking the procedure, writes the editor of Harvard Health.

Not only are these and other tests a waste of money, they also may be detrimental to the health of the patient.

Eight more medical specialty organizations are planning to join the campaign, says Harvard Health.

READ the top 18 procedures to use with caution at Harvard Health Publications, or visit ChoosingWisely.org to download the full lists from each specialty area of medicine represented so far.