Forget the style, what about the substance: how they performed on the questions that mattered most

The NHS

By Jeremy Laurance, Health Editor

For what is traditionally a key election issue, the responses to the NHS question were dismal.

Cameron repeated his misguided call for all cancer drugs to be made available if a doctor recommends them, Clegg foolishly demanded a halt to closures of A&E and maternity departments and Brown repeated a guarantee of quick access to tests and treatment, already enshrined in the NHS constitution.

The leaders struggled to find differences on health. Cameron said cancer drugs are more widely used elswhere than in the UK so Nice (the National Institute for Clinical Excellence) should be bypassed to allow doctors to make individual decisions.

Nice ensures the NHS gets value for money, and has forced cuts in cancer-drug costs. If Cameron has his way, scarce NHS resources will be spent on one group, cancer patients, at the expense of others.

Closing A&E departments and maternity units is politically unpopular. But keeping smaller units open costs lives. Research shows that patients treated in larger hospitals by doctors with more experience have better outcomes. If Clegg's view prevails, people will rejoice that their local hospital has been saved, but more people will die.

The economy

By Sean O'Grady, Economics editor

Much of the argument between Gordon Brown and David Cameron about "waste" – the £6bn in savings the Conservatives claim to have identified to reduce the NationaI Insurance rise – was irrelevant.

Mr Cameron was right to say that every family and business looks to "get more from less", but if there is £6bn less being pumped into the economy then, in macro-economic terms, it doesn't matter if it's being chucked out of helicopters; the impact on demand is still going to be depressing when it disappears.

That could, as Mr Brown claims, risk a double-dip recession; it could also, as Mr Cameron says, save the nation from losing its cherished AAA credit rating. That would probably push insurance firms and banks into crisis and mortgage rates through the roof.

Nick Clegg had the best of the argument about detail, but he is making heroic assumptions about what he can get from tax dodgers. All parties are between £15bn and £50bn adrift on cutting the deficit. As usual, we'll get told the truth after polling day; no one ruled out raising VAT, which said it all.

Education

By Richard Garner, Education editor

A teenager who asked why pupils were being "over-examined and under-taught" got short shrift from the party leaders on the first part of the question.

Gordon Brown underlined the need for today's youngsters to be as well qualified as as those in Asia and America, making it clear today's youngsters needed the grades to be able to compete in the modern world.

David Cameron uttered some warm words about the need to "open young minds" as well as test youngsters, and Nick Clegg told the teenager he thought "everybody would recognise what you're talking about".

There was no commitment from any of the three for any specific reduction in testing or examinations. Differences did emerge was on the second part of the question. Nick Clegg would give schools enough resources to reduce class sizes in primary schools to 20 and secondary schools to 16 as part of its £2.5bn "pupil premium" for disadvantaged youngsters.

Gordon Brown sought unsuccessfully to wring a pledge from David Cameron that he would promise to protect front-line spending on schools. David Cameron did promise to be ruthless in scrapping education quangos, now costing £300m a year.

Defence

By Kim Sengupta, Defence editor

The only real note of interest about defence in last night's debate was that it was the one answer Nick Clegg appeared to fluff. His attempt to say why the Trident nuclear deterrent should be scrapped was stumbling, with him reduced to saying at the end " All I am saying is ..."

The rest of the time on the topic was spent on whether British troops in Afghanistan were under-equipped. Camer-on accused Brown of failing to ensure enough helicopters and Brown claiming that the need for them became apparent only after the "Taliban changed its tactics" to "explosive devices" and "guerrilla warfare". This was wrong. But Cameron was too busy declaring he has been to Afghanistan several times – day-trips for photo opportunities – and Clegg repeating that everything would be solved if only Trident was got rid off.

Brown insisted the commanders on the ground had everything they had wanted. But the new armoured vehicles keep getting blown up by bigger bombs. None of the three mentioned the grim facts, that there is no foolproof security against the bombers, and that there will be more casualties.

Crime

By Mark Hughes, Crime Correspondent

On crime and policing all leaders appeared to hold broadly similar views. "We've got to get the police out on the streets," David Cameron said. Nick Clegg, whose party has said exactly how they will increase police-strength by 3,000 officers (by scrapping the national ID card scheme), agreed.

Gordon Brown said his Government had introduced rules to make this the case. "Police have to spend 80 per cent of their time on the streets," he said.

But the argument is one which frustrates senior police officers. Hugh Orde, president of the Association of Chief Police Officers, said: "They say the solution to everything is more cops on the street: well, no it isn't. It is quite scary if people who are claiming to represent communities see the solution simply as more cops on the street while all the evidence shows that if you're a patrolling officer the chance of coming within half a mile of a burglary is about once every 150 years."

It was perhaps a good opportunity for one of the politicians to point out that while more officers can only be a good thing, simply having them walking the streets, rather than involved in intelligence-led operations, is not going to solve much. Instead, none of them chose to lift the debate.

Immigration

By Robert Verkaik, Home Affairs Editor

Immigration is a potentially explosive issue with the three parties at odds over the best way to control the numbers of refugees and migrant workers coming into Britain. Gordon Brown's contention that "net inward migration" is finally falling after years of steady rises was dismissed by the others as too little, too late.

Nick Clegg suggested it was impossible to say whether this was true without means of counting how many illegal immigrants had left the country voluntarily. He said immigrants should be sent only to those parts of the country where they can be properly accommodated.

David Cameron said his party was committed to imposing a cap to "bring immigration down so it's in the tens of thousands, not hundreds of thousands". Brown said: "I agree with Nick: an arbitrary national cap will not work and the Conservatives are not even giving the number for that cap so they can't tell us what they will do."

Clegg wondered what would happen when the cap is reached and Manchester United or Chelsea want to sign a new foreign player from outside Europe?