Nearly three years after the Dawson College shooting, a study has found 40 per cent of the school's community was still grappling with mental health problems.

The study, which is the first to look at the psychological impact of mass shootings, involved 949 members of the Dawson community.

Researchers found two per cent of students were still in a state of post-traumatic stress after the Sept. 13, 2006 incident, which left student Anastasia DeSousa dead and 20 others injured.

Another seven per cent of respondents reported having symptoms of post-traumatic stress and 12 per cent reported having severe depression.

Some students and male support staff also reported a reluctance to seek psychological assistance due to the fear of being stigmatized by friends and loved ones.

"People were disinclined to seek help because of prejudices related to mental illness, fear of showing weakness or appearing vulnerable to one's peers or boss and the false perception that time would solve everything," Alain Lesage, a professor of psychiatry at the University of Montreal, said in a press release.

James Santos, the student used as a human shield by gunman Kimveer Gill, says he still thinks regularly about that day.

Santos cradled an unconscious Anastasia De Sousa in his arms after she had been hit several times by the bullets of a semi-automatic rifle. He unsuccessfully begged the shooter to allow him to get her medical care.

"After I got a bit of the help ... everything went away and I sort of brought myself back," Santos told The Canadian Press on Monday.

"I just always have it in my mind and it's always going to stay in my mind, but that's something that I've got to deal with for the rest of my life."

For Santos, the psychological pain didn't really sink in until a few months after the attack. He was lucky and sought help, though the study shows that 70 per cent of those who reported post-crisis symptoms did not.

"I try to tell my friends, 'It's over, it's over now. There is nothing we can do about it now," said Santos in an interview with CTV Montreal. "I tell them that talking to anybody, not just professionals, is another way of getting closure."

Santos has graduated from Dawson and is now eyeing a career as a police officer.

Overlooked groups

Researchers also found that certain groups -- such as cafeteria staff, college support staff and those who were hospitalized -- were overlooked after the event and the repercussions of their psychological damage was underestimated.

In addition, some professors reported feeling powerless and incapable of helping students.

"Since the 1999 Columbine tragedy, school shootings have doubled (to 60), compared to the last decade, resulting in 181 deaths," Dr. Warren Steiner, head of the McGill University Health Centre's Department of Psychiatry, said in a press release.

"Despite the frequency of these incidents, there are very few empirical studies on their psychological effects and no studies have evaluated the effectiveness of psychological interventions."

On April 20, 1999, two high school students in Columbine, Colo., stormed their high school carrying shotguns, a rifle and a semi-automatic. They killed 12 classmates, a teacher, and wounded 23 others, ending the massacre with their own suicides.

At Dawson College, Kimveer Gill used a Beretta CX4 Storm semi-automatic carbine, and a handgun in the violent rampage -- weapons he acquired legally.

In total, he fired 72 times with the semi-automatic rifle and six times with a handgun.

He was eventually wounded by police, but managed to take his own life before they could make an arrest.

"It is crucial that we learn from these experiences in order to better help those affected by such tragedies," Steiner said.

Steiner is one of the key figures involved in implementing an emergency psychological intervention plan following the shooting at Dawson College.

The study did find that more than 80 per cent of respondents who received care reported that they were satisfied with those services.

With a report from CTV Montreal's Herb Luft