Care inspectors gave advance notice of their visits on just one occasion in 25 last year, new figures have revealed.

Only 4% of visits from the Care Inspectorate were announced in 2012-13, compared to 41.2% in 2010-11.

Virtually all inspections of care homes for the elderly last year were unannounced, with 98.6% of such visits in this category – up from 52.4% in 2010-11.

The Care Inspectorate checks on a variety of care services, including homes for the elderly, nursing homes and childminders.

A total of 8839 inspections were carried out last year, of which only 352 were announced.

On 64.4%, of occasions the inspectors turned up completely unannounced, and 31.6% of inspections were announced at short notice.

Such inspections are typically used when care services are provided in either a private home or in changing locations, with inspectors phoning to establish where people will be, giving only minimal notice of their visit.

Annette Bruton, chief executive of the Care Inspectorate, said: "Virtually every care home now faces unannounced inspections – whether they support children, adults or older people – as do almost all nurseries.

"No system of inspection can guarantee that bad things will never happen to vulnerable people, but unannounced inspections are absolutely essential.

"They are a key way of testing how well a care service is actually performing."

She added: "Our job is not just to inspect care services: it is to help them meet the highest standards.

"The public rightly demands the highest standards and so do we."