In our new report with the Health Foundation, we consider five key approaches often raised in discussions about funding social care – improving the current system, the 2017 General Election Conservative proposals, a single budget for health and care, free personal care (as in Scotland) and a hypothecated tax.

We consider all five against a range of attributes from equity and fairness to, perhaps unusually, the challenge of implementing any change. We look here in particular because poor public understanding, combined with potentially high political and economic costs of change, has led successive governments to avoid grasping the challenge of social care funding.

Unsurprisingly, improving the current system continues to score highly on ease of implementation. The relatively small changes that are possible within the current model – changes to financial eligibility thresholds (untouched since 2010) or extending the precept still further – are relatively simple and cause little disruption. The current model also attempts to focus limited resources on those with the greatest needs and fewest means.

Of course, its failings are all too obvious: it is complex, poorly integrated with health, has wide variations in provision and requires those with modest wealth to pay their own cost while failing to protect them against catastrophic cost. Not for nothing did we initially refer to improving the current system as 'muddling along'.

Would the Conservative Party proposals at the last election have improved on this system? We find they are significantly more generous than they were, perhaps given credit for at the time. Yet this generosity is largely focused on those with assets between £23,250 (the current upper threshold) and £100,000 (the proposed new one).

One group in particular – those with few assets other than the value of their homes – are at risk of losing out because, for the first time, housing assets are included in the means test for home care.

The system is also in some ways – especially given its plans for a cap on costs – more complex than the one it is trying to replace and is silent on key issues including alignment between health and care.

Better alignment is, of course, a key aim of our third approach – a single budget for health and care – and overall we do see pooled budgets as potentially representing significant progress to aiding joint working between the sectors.

Single budgets do not in themselves guarantee integration or make any changes to wider entitlement to social care. Indeed, there is some risk that money from social care might be redirected to acute and emergency services when these are under pressure. While this option may be a more efficient way of spending money, it does nothing to raise it.

Free personal care, similar to the model offered in Scotland, scores strongly around equity since care is provided based on need only and without charge. It is also one of the simplest for people to understand and, unsurprisingly, has been popular. But this has been increasingly expensive in Scotland and, as with integration, does not in itself, raise any money.

Finally, we consider what is perhaps the concept of the moment – a hypothecated tax for health and social care, which has now been suggested by a range of commentators and is already practiced, in soft form, with the social care precept.

Hypothecation itself is neither fair nor unfair – it depends upon the progressiveness of the taxes used to raise the money. There are arguments in favour around sustainability of funding, simplicity and public acceptance. But we also see risks around integration and caution that hard hypothecation would require a very significant disruption to the current system.

We do not reach conclusions or make recommendations in the report, but rather aim to present the pros and cons of each option. As we once again enter green paper territory, it is critical we consider coolly and clinically how we can best create a social care system which is fair, efficient, sustainable, accountable and easy to understand.

We need a system that stands a better chance of being implemented than all the other proposals made over the last two decades which have been the subject of high hopes but failed to deliver real change.

Simon Bottery is a senior fellow focused on social care policy at The King's Fund