G8 LEADERS resolved this week to tackle dementia head on, but a leading Scottish neuropathologist says rugby has a significant part to play.

And if the sport fails to learn self-evident lessons now, it might have to consider amending its rules in the future.

A former prop with Cambuslang, Dr Willie Stewart, who is based at Glasgow's Southern General Hospital, was involved in research which revealed the first confirmed case of early-onset dementia caused by playing the sport. Abnormal protein levels exceeded those found in boxers with punch-drunk syndrome.

"This is now a major public health issue," Dr Stewart said. "Here is a preventable cause of dementia that we could be doing something about, considerably reducing the incidence of the problem. Unlike other forms of dementia, we can almost predict it. You look at a team of rugby players - guys injuring their brains over and over. Maybe we can get a handle on what happens in brains that have developed dementia. In other forms, by the time you research it the person already has dementia. Here we can track people from rugby retirement to later life, and try to figure out what happens to the brain."

The Herald aired issues of brain injury in high-impact sports last week, including concerns that rugby could face litigation similar to that which has forced the NFL to pay $750m in compensation and tens of millions more bank-rolling research.

Now, the Scottish government are tackling the issue. A booklet about concussion is being prepared for every school and sports club. The Irish and Welsh governments, and the Westminster all-party sports group, are watching closely.

The document, prepared by the Scottish executive, sportscotland, Scottish Rugby Union and Scottish Football Association, will be released early next month with the most basic message: "If in doubt, sit them out".

"I would not want to impair rugby, or change the game," Dr Stewart said. "It's a great game, but we should enforce what is best practice now."

Exclusion for 15 days used to be mandatory after concussion but a five-minute pitchside assessment is now being trialled. Dr Stewart and many rugby medics claim this is flawed. He said: "Pitchside assessment is being heavily promoted by the International Rugby Board, yet before they have completed the study, and before the data has been reviewed. They are saying it's a huge success. I think there are real questions as to whether that's true. People are being pressured to adopt this test. I've spoken to medics from just about every union. Few are comfortable with a five-minute test. Everybody thinks 15 minutes at least."

Dr Stewart was in Dublin yesterday, on a panel at a conference on sport concussion. Among the speakers was the medical officer from the Irish Jockeys Association. He told of a recently thrown rider. "After five minutes he was perfectly lucid," recounts Dr Stewart. "After 10, he was completely disorientated. Two hours later he was in hospital with bleeding in his brain. If it had been rugby, he'd have been back on the pitch and 10 minutes later would have been in a coma."

He is irked that the international board's chief medical officer, Martin Rafferty, has said the IRB is leading concussion research because nobody else in the world is capable of doing it.

"I've been involved in brain injury research for more than a decade," Dr Stewart said. "There's an annual conference attended by 600 people who research every aspect of it. I could put him in touch with 10 people round the world who could do it. Instead, the IRB are funding a study at Auckland University of Technology. Concussion, and long-term psychological and dementia issues are fantastically difficult to diagnose and understand. To research it, you need people who are really, really informed.

"The research is proposed by rugby unions and rugby boards. I think that's a very bad idea. The tobacco industry did its own research and concluded smoking did no harm. American football did research into concussions for 10-12 years and said there was no problem.

"When people went back and looked at the data, it showed a 20-times increased risk of early-onset dementia in retired footballers. One of the lead authors on the Auckland research is Dr Rafferty. The research should be done but it should be independent of the rugby."

"We need to look at training," added Dr Stewart. "According to some of the guys, the impact in training is as vigorous, if not more so, than in a match. Never mind concussion, every time they bang into a ruck, there's another little injury in the brain.

"The players' union persuaded the NFL to adopt no-impact training. Head injuries dropped by more than half. It's clear from our meeting in Dublin that this side of the Atlantic is some way behind in accepting and understanding the issues. Education and medical staff education is nowhere near where it should be."

The Holyrood initiative includes a survey of assessing the school and sports clubs leaders' impressions of concussion. Dr Stewart: "A lot of people think you have to be knocked out, and a lot of people still believe concussion gets better in a day or two. It does not. And sub-concussive blows still injure the brain.

"We need to make kids and parents aware of what concussion is, what the problems might be, and we need to make certain that three weeks out means three weeks out. Current practices should be applied vigorously, with full education and information. If that does not produce results and we still see significant problems, then we have to wonder whether we should change the rules."