VANCOUVER - A new study suggests a safe-drug-injection site in Vancouver that has been hailed by scientists as a success is really a failure.

The study, published Wednesday in the Journal of Global Drug Policy and Practice, says there are serious problems in the interpretation of findings about Insite -- the first such facility in North America -- which opened as a pilot project over three years ago.

At Insite, addicts shoot up their own heroin or cocaine under the supervision of a nurse who provides clean needles.

Proponents of the facility say it reduces overdoses, crime and HIV risk behaviour among injection drug users, who often share needles on the street.

But report author Colin Mangham, director of research with the Drug Prevention Network of Canada, refutes such claims, saying positive findings about Insite have been overstated while negative ones have been ignored.

"(The findings) give an impression the facility is successful, when in fact the research clearly shows a lack of program impact and success."

Randy White, president of the Drug Prevention Network of Canada, said Mangham's study provides useful information that could affect Insite's future.

"There are people in Vancouver and throughout the country who do not agree with the project and would like to see a balancing of the reports and evaluations and I think this is the first time and I think that's good," he said.

White said prevention and treatment are the best options to deal with drugs.

His group is working with the Alberta Alcohol and Drug Abuse Commission and the Canadian Centre for Substance Abuse to develop a national drug policy, White said.

Other studies published in top medical journals including the Lancet, the British Medical Journal and the New England Journal of Medicine suggest Insite has led to reduced public disorder, crime and overdose deaths.

"We do not know if any of the overdoses would have resulted in death outside the site," Mangham says in his study.

"The number of overdose deaths in Vancouver and the Downtown Eastside has increased since Insite started up. This site at least suggests that in its three years of operation Insite has produced no impact on overdose deaths."

Mangham also says a study published in the American Journal of Infectious Diseases in 2005 about the reduction in shared needles among addicts using Insite is misleading.

"Only exclusive use of Insite correlates with reduced sharing," he says. "If someone uses Insite for all their injections, it goes without saying they would not share needles. Only one in 10 HIV negative participants reported using Insite for all their injections."

According to the study, public disorder and crime were reduced because of increased police presence, not because of the facility's presence.

The Conservative government has extended an exemption that allows Insite to operate legally until Dec. 31, saying more research is needed to determine how to get addicts off drugs.