As we enter the final 100 days of a referendum campaign which we hope will end with a vote in favour of Scottish independence, it seems a good time to ask what the Yes campaign and the Scottish Government have to do to achieve that result.

The Yes Scotland campaign has done a creditable job through social media and local networking to encourage the growth of a real grass-roots movement. Young people in particular appear to be getting involved in politics in a way few thought was possible in this apathetic age. However, the message is still not getting through to two significant groups: women and the over-55s. The future of Scotland is very much in their hands.

Last week's Ipsos MORI poll showed a narrowing of the gap between Yes and No, and revealed that Scottish men are more or less split 50-50. But women remain No voters by a margin of two to one. It is not entirely clear why this gender divide should be the case. It is claimed, rather patronisingly, that women are more cautious and risk-averse.

The Scottish Government hoped that the promise in the independence white paper to introduce free childcare would have attracted the female vote. But there appears to be a credibility gap and a fear that these pledges have not been properly costed. Which makes it more important than ever that the Scottish Government should be addressing the very real concerns about the possible cost of independence.

The influential Institute for Fiscal Studies (IFS) claimed last week that an independent Scotland would have to impose austerity spending cuts or increase taxation because there would be an £8 billion deficit. It is true that the IFS has been saying this for many months, and that it has said the same about the UK. But it cannot be dismissed. If Scottish Finance Secretary John Swinney can't put a figure on it, others will.

The IFS didn't take into account the impact of immigration, job creation, oil investment etc. Surely, it is up to the Scottish Government to quantify these, or at least provide a different narrative.

Beyond that, work needs to be done to challenge the claim that Yes means separation, the break-up of Britain, the destruction of the UK - what might be called the Barack Obama view of independence. Alex Salmond is correct when he argues in a piece in this newspaper today that self government does not mean destruction; it means democratic renewal. Scotland isn't going anywhere. It will still be part of Britain, part of Europe, part of the world. The only difference would be that under independence Scotland would get the kind of governments it has been voting for.

It would also be helpful if more Government ministers were seen to be active more often. There has been a lack of activity at the ministerial level which is puzzling many in the broader Yes campaign. Whatever happened to front-rank campaigners like ministers Roseanna Cunningham and Mike Russell?

There have been claims the Yes camp has been worried about peaking too early. In the 100 days ahead it's time to throw caution to the wind.