It is “not clear” how major reforms to adult social care pledged by the Scottish government will be paid for, the country’s public spending watchdog has said.

Antony Clark, Interim Controller of Audit at Audit Scotland, said in a blog that it would be a mistake to focus on organisational change at the expense of improving people’s experiences.

Earlier this week newly-appointed Health and Social Care Secretary Humza Yousaf promised a national care service would be up and running in the next five years.

It follows an independent review, headed by Derek Feeley, proposing a series of reforms including the abolition of remaining social care charges and better pay for staff.

Derek Feeley said the cost of delivering all his recommendations would be an extra £660m a year on top of existing spending projections, most of which is made up of expanding access to social care, with a price tag of more than £400m.

Other changes include £50m on cancelling non-residential fees and more than £100m to reduce charges for self-funding care home residents.

But Audit Scotland believes that “more detailed work” is needed to understand the true cost of these new approaches, as well to determine whether demand for services would increase after charges were removed.

Concerns have been raised that government funding has failed to keep pace with previous moves to introduce free personal care for over-65s and then under-65s.

Derek Feeley raised the prospect of tax increases in his report but did not specify a particular approach, prompting suggestions of an “elephant in the room”.

The watchdog adds lessons need to be learned from the integration of health and social care, which it states has “moved too slowly” and been “challenging in practice”.

Audit Scotland says it will publish further work this year looking at the “challenges and risks” of the new model being proposed.

Read more: Social care review: What does the report say?; ‘Top down’ care review plans branded ‘huge mistake’; SNP commission backs care home buyouts

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