Countries which elect their governments using proportional voting systems have higher turnouts among voters than those using first-past-the-post, electoral specialists have found.

Nations using PR had average turnouts of 70 per cent - 10 per cent higher than those, such as Britain, which use non-proportional systems.

The analysis of turnout in 164 countries, by Professor Pippa Norris of Harvard University, was seized on yesterday by MPs who said PR may be an answer to addressing the worrying lack of voter engagement in the UK.

Writing in The Independent, Professor Norris, a world authority on electoral systems, said switching to PR for a general election would "probably significantly strengthen British turnout".

She cites turnouts in countries such as Sweden, Iceland and Israel where more than 80 per cent of people of voting age go to the ballot box.

The findings come as The Independent's Campaign for Democracy gathers pace, with nearly 38,000 readers calling for urgent reform of the electoral system.

Ms Norris said there was evidence that introducing PR made the public feel their votes were not wasted and that "the basic type of electoral system does indeed shape the incentive to participate".

She said that "the basic type of electoral system remains a significant indicator of turnout".

Ms Norris said results of studies "confirm that average turnout was highest among nations using proportional representation, namely party list and the single transferable vote electoral systems".

The lack of public interest in last month's general election has alarmed all three political parties. Turnout was 60.9 per cent, slightly up on 2001, although more people voted in marginal seats where there was a high-profile contest.

Lord Falconer of Thoroton, the Secretary of State for Constitutional Affairs, addressed Labour MPs on Monday about ways to increase voter participation, including postal votes.

Yesterday, in a debate on electoral reform in the House of Commons, MPs said the issue of turnout was vital to the health of our democracy. John Hemming, the Liberal Democrat MP for Birmingham Yardley, quoted statistics showing that G8 countries which use PR had turnouts 20 per cent higher than in Britain. He said "the key to boosting turnout is proportionality" and that in G8 countries with PR turnout was 80 per cent.

Other MPs called for an end to the "electoral lottery" which allowed Labour to return to power with a working majority, despite gaining only 35 per cent of the vote.

Speaking for the Government, Harriet Harman, the Constitutional Affairs minister, acknowledged that the debate on electoral reform was "hugely important" and there were many people with "deeply held views" on the issue. She said the Government needed to look abroad to study the effect of PR systems on turnout as well as within Britain. She added that the Government's review was already looking at effect on turnout.

"We have to look at our own system but also the trend, and we have to look abroad at the effect of different voting systems on turnout," said Ms Harman. "The question of turnout is affected by many more things than simply the clarity and fairness of the individual voting system."

She said she thought the "trend in turnout in proportional systems seems no better than those used in first-past-the-post."

Ms Harman said discussion about PR should be about "improving democracy" and not driven by "party political interests". But she said there was no voting system that "hits all the objectives" - otherwise it would used all over the world.

She said: "The question is what is the best system which has the support that commands legitimacy and is seen to be fair?"

John Barrett, the Liberal Democrat MP for Edinburgh West, paid tribute to The Independent for its Campaign for Democracy which he said had mobilised a significant degree of public support. He said it was "an excellent campaign, not just for raising support, but for seeking to educate people". Mr Barrett said the "decline in voter participation" was a serious problem that needed to be addressed.

Politicians on Britain's voting crisis

Lord Falconer: 2004

"Britain certainly has a problem with turnout. But it is far from the only country which does so... People feel the decisions they make have a greater or at least a more direct impact locally."

Alan Milburn: On 2005 Election

"This is an election about turnout. The worry for us is that propensity to vote among Conservative voters seems to be higher than the propensity to vote among Labour voters."

Tony Blair: After 2001 victory

"If people really wanted to put the government out, they wouldn't be staying at home, they would be out putting the government out."

Michael Howard: 2005

"We [politicians] are probably the main people to blame [for falling turnout] because it's up to us to persuade people that politics is relevant to their lives."

Shirley Williams: 2001

"If [Labour] cannot attract their own voters... one must seriously question if this is a mudslide, not a landslide. This shows a steady loss of faith in the political process."