By Jeannie Blaylock, First Coast News

Can science prove service dogs help suicidal veterans with PTSD? The non-profit K9s for Warriors, which trains rescue dogs for warriors, is announcing a new study. It could be the first step in scientific documentation the dogs do work.

Executive director Rory Diamond says, "This is amazing. This will blow the lid off everyone looking at PTSD because we are proving for the first time that a service dog changes our warriors' brain."

Diamond says K9s For Warriors began working with researchers at Purdue University's College of Veterinary Medicine back in 2013.

The first phase of the research is now published in the Journal of Consulting and Clinical Psychology.

Lead researcher, Dr. Maggie O'Haire, assistant professor of human-animal interaction at Purdue, told First Coast News by Skype the study shows service dogs do have a positive impact on the veterans with service dogs.

She explains, "The conclusion of this study is that veterans with service dogs have lower PTSD symptoms, lower depression, lower anxiety and increased ability to participate in social activities outside of the house."

Dr. O'Haire says the findings in this first phase were based on extensive surveys with 141 veterans around the country. "This is scientific data to document changes in a standard, measurable way," she explains.

She says never before has there been a scientific study to prove the service dogs do work. In this first phase of research the dogs were considered part of the veterans' current treatment plan.

Why does all this matter? Diamond says "for ages" the VA has denied paying for service dogs on the basis no scientific proof existed that they help veterans manage PTSD. Now Diamond says the VA will have to pay attention to the study.

Up until this point we've heard numerous testimonies from graduates of K9s for Warriors. For example, James Rutland says without his service dog, "I'd be dead." He was planning his suicide.

But stories aren't enough to satisfy scientists.

Dr. O'Haire says she's "excited" the National Institutes of Health will now participate in the coming phases of the research. She says the NIH accepts few applicants in their funding of research and the fact they've chosen to get on board shows the importance of the findings so far.

The next phase involves, for example, saliva tests from veterans at K9s for Warriors and around the country. The spit can help researchers measure cortisol levels. Dr. O'Haire explains that cortisol is hormone that shows the level of stress someone has.

Most of us wake up with a jolt in the morning as we face the day's stressors. Our cortisol levels spike in the morning. Not true with veterans with PTSD because many are up at night with anxiety and nightmares.

But with service dogs warriors say they sleep better. The research may show their levels of cortisol spike -- as they should -- in the morning.

Dr. O'Haire says the next research findings should come out in 2018. Purdue is still collecting saliva samples and conducting other parts of the study..