Four out of 10 hospitals advertise robotic surgeries on their website homepages, and many of them tout their superiority over conventional procedures. But despite these claims, there is no scientific evidence proving that robotic surgeries are safer or more effective than regular surgery, according to a new study.

There are 10 randomized controlled studies (the "gold standard" for testing scientific validity and effectiveness) regarding robotic surgeries , but none of them show that robotic surgery is better than traditional surgery, said study researcher Dr. Marty Makary, an associate professor of surgery at the Johns Hopkins University School of Medicine in Maryland. During a robotic surgery, a surgeon uses a computer to move instruments that are attached to robotic arms.

"No study has demonstrated an improvement in postoperative complication rates," Makary told MyHealthNewsDaily. Oftentimes, hospital websites made claims based on studies unfairly comparing robotic surgery to the more outdated open surgery, which is when the surgeon cuts open the skin to gain direct access to the internal organs.

However, the websites don't often mention robotic surgery's effectiveness compared with the more commonly used minimally invasive surgery, which is associated with better outcomes than open surgery, said Makary, who is also the author of an upcoming book on transparency in medicine.

The study was published May 18 in the Journal for Healthcare Quality.

What's on the websites

Makary and his colleagues evaluated the websites of 400 randomly chosen U.S. hospitals (with 200 beds or more) and found that 41 percent of hospitals advertised robotic surgery.

Of those advertising robotic surgery, 89 percent had a statement on the website saying that robotic surgeries were better than traditional surgery. For example, 85 percent of websites said robotic surgeries are less painful, 86 percent said they have a shorter recovery time, 80 percent said they result in less scarring and 78 percent said they result in less blood loss than traditional surgeries, the study said.

And 32 percent of the hospital websites said robotic surgeries improved the outcomes from surgery for cancer, the study said. None of the websites mentioned risks involved with robotic surgery.

Seventy-three percent of the hospital websites had materials online that were provided by the robot manufacturer, the study said.

"The robot manufacturer aggressively markets to hospitals and has Web-ready website content on a DVD, which they offer to hospital marketing departments," Makary said. "The material provides patient information on robotic surgery [and] images, and often does not state risks or the added costs or operation time associated with robotic surgery."

A 'scary trend'

This new study identifies a "scary trend": that hospitals are using industry content on their official websites and not disclosing the source, Makary said.

"This marks the first time we have seen industry author and create patient information on official hospital websites without disclosure," he said.

In the future, it's likely that robotic surgery will mature and then be shown in studies to provide added benefit to patients, Makary said. But right now, those studies aren't showing any improvements in reducing postoperative complications, he said.

Pass it on: Many hospitals promote robotic surgery on their websites, but there aren't clinical trials to back up robotic surgery's increased effectiveness over other more traditional procedures.

Follow MyHealthNewsDaily staff writer Amanda Chan on Twitter @AmandaLChan.