The difference in overall body weight lost was 3 percent between the device group and the sham device group, according to the study. Schauer questions whether that's enough of a difference to recommend the device over diet and exercise.
"For this device to be competitive it has to come between the weight loss we are getting with surgery and drug therapy," he said.
Weight loss is generally 8 to 10 percent of body weight with currently available drugs for weight loss, Schauer said. Weight loss with surgery is in the range of 25 to 30 percent, he said.
"So with a device like this, which is lower risk than surgery but greater risk than taking a pill, it needs to achieve an additional 15 to 20 percent weight loss," Schauer said. "It falls below expectations."
On a positive note, fewer patients had serious side effects related to the therapy than the researchers expected -- about 4 percent rather than the anticipated 15 percent, according to the study. Common side effects attributed to therapy were heartburn, indigestion and abdominal pain.
The device is being considered for approval by the U.S. Food and Drug Administration, Billington noted.
"If it is approved, it would be the first device for obesity treatment approved in 10 years and could provide an additional treatment option beyond the currently available medication and surgery," he said.
In another study in the same journal issue, an analysis of all the weight loss surgeries done in Michigan found that sleeve gastrectomy has become more common than Roux-en-Y gastric bypass surgery.
Both Roux-en-Y gastric bypass surgery and sleeve gastrectomy are types of weight loss -- or bariatric -- surgeries that make the stomach smaller. In a sleeve gastrectomy, a large part of the patient's stomach is removed. In a Roux-en-Y gastric bypass, a part of the stomach is used to create a pouch -- essentially a new smaller stomach.
Although long-term outcomes of sleeve gastrectomy are still unclear, it might be more popular because it seems to have a favorable safety profile. And, weight loss may continue for at least two to three years after the surgery, the researchers said.