Young people continue to be the focus of police searches despite turning up the fewest illicit items, according to Police Scotland's public scrutiny body.

There has been a substantial decline in stop and search activity since government advisers raised concerns about its widespread use as a "default tactic", a Scottish Police Authority (SPA) update found.

The Advisory Group on Stop and Search, chaired by John Scott QC, also recommended "consensual or non-statutory stop and search of the person in Scotland should end" once a new Code Of Practice is drawn up.

The Scottish Government has yet to produce a timetable for the new Code of Practice and consensual searches are still being conducted.

The advisers warned that stop and search "has been used disproportionately, particularly on children and young people".

The SPA found that there continues to be a significant number of both statutory and consensual searches on under-17s.

Teenagers are targeted the most despite being the least likely to be found with anything - while people in their late 20s are targeted the least despite being the most likely to be carrying something.

The number of total searches between June and August 2015 was approximately 97,500 less than the total recorded within the same period during 2014 - a reduction of more than 81%.

Children aged 12-15 saw the lowest proportion of total searches (8.5%) and positive searches (12.6%) overall.

Outside this demographic, people aged 16-19 saw the most searches (22.1%) but the fewest positive searches (18.8%).

People aged 25-29 saw the fewest searches (12.8%) but the most positive searches (28.1%).

There is a similar pattern with statutory searches - those conducted without consent under suspicion of carrying items such as weapons, drugs, stolen goods or alcohol.

More than 20% of statutory searches were on 16-to-19-year-olds, with items found in nearly a quarter (23.9%) of searches. However, just 13.6% of statutory searches were on 25-to-29-year-olds, with items found in a third (33.3%) of cases.

No consensual searches of children under the age of 12 were recorded but officers conducted three searches on children below the age of 12 using legislative powers in relation to the misuse of drugs, stolen property, and bladed weapons respectively.

The report does not say whether these searches were positive.

Last week, the SPA heard that some police officers still perceive that they are under pressure to meet stop and search volume targets.

The force insists officers have never been given such a target but it found some "are confusing directed and targeted patrols with general pressure to conduct searches".

The latest update was published on the SPA website to comply with the Advisory Group's complaint about "problems regarding the release and availability of data".

It stated: "Although not directly comparable with previous years, it is clear that the ratio of consensual searches to statutory (or legislative) searches has reversed from past years, with the proportion of searches which are consensual now substantially lower than those which are statutory.

"Detection rates were significantly higher for statutory searches."

It added: "There is a significant variation in rates of stop and search per head of population between the North, East, and West Command areas and even between neighbouring local authorities within command areas.

"Search rates within each Command do, however, tend to be higher in local authority areas where rates of violent crime are also relatively higher.

"The majority of searches continue to occur in the West Command area, although the proportional value (compared to the East and North) fell slightly between June and August 2015.

"Most seizures take place in the West Command, and pertain to alcohol.

"The majority of recorded alcohol removals resulted from seizure rather than stop and search.

"Young people continue to be a focus of search activity. The number of stop and searches recorded between June and August peaks across 16-to-18-year-olds.

"The most prevalent ages for searches skew even younger, peaking for 15-to-17-year-olds.

"The detection rates for younger people are considerably lower than for adults, specifically those between 20 and 40."

The high number of consensual searches on the young "may suggest the 17 and under group are less likely to refuse a search", it stated.

Police Scotland has recognised that "there is still more to do" in its progress on stop and search.

Since March 2015, it has introduced a public advice slip, online information and enhanced data capture.

It said the code of practice is still pending and there has been a reduction in the rate of consensual stop and search

Assistant Chief Constable Mark Williams said: "As our recent improvement plan update showed, the service has made really positive progress in relation to stop and search.

"Police Scotland has been working hard with a wide range of stakeholders, including young people, to make improvements and, whilst there is still more to do, the update recognises just how far we have come.

"Our focus will continue to be on fully completing our improvement work and on ensuring that stop and search is used on an intelligence-led basis as a proportionate and effective policing tactic."

A Scottish Government spokeswoman said: "The recently published Police Scotland improvement plan outlines the significant progress that the service has made in improving its practices around stop and search and, in particular, the extensive work that has been done to take forward the recommendations set out in the initial report including discussions with equalities and human rights organisations, the Scottish Children's Reporter Administration and Scotland's Commissioner for Children and Young People.

"As well as work to undertake improved recording practices and a new national stop and search database, it is particularly encouraging to see the significant and continued increases in the proportion of statutory searches taking place.

"We will continue to liaise with Police Scotland and the Scottish Police Authority to take forward the next steps, including consultations on the draft Code of Practice and on whether the police should have the power to search young people under 18 for alcohol."

An SPA spokeswoman said: "The publication of our first quarterly Assurance Report on Police Scotland's use of stop and search is an important part of the strengthened monitoring and governance of this tactic in Scotland.

"The publication is a direct response to recommendations aimed at enhancing openness and transparency contained in the SPA's Scrutiny Review of 2014 and the Advisory Group's Report on Stop and Search Chaired by John Scott QC last August.

"To date, our Scrutiny Review has played a key role in underpinning the subsequent improvements to practice and policy. We have already seen strengthened processes and intelligence, enhanced engagement, and improvements to officer training. The Authority will continue to formally govern the implementation of improvements to stop and search to ensure all relevant recommendations are progressed and monitored."

Graeme Pearson, Scottish Labour's justice spokesman, said: "The continued controversy over the use of stop and search by Police Scotland is a reaction to the dysfunctional target culture encouraged by the SNP Government over many years.

"The resultant loss of public trust on this issue alongside the on-going need to provide community safety needs careful consideration before deciding public policy for the future, particularly as it affects those communities living with crime in their midst.

"I would welcome some additional analysis and professional comment on the current situation to enable options for the future to be delivered in light of John Scott's recommendation."

John Finnie, justice spokesman for the Scottish Greens, said: "It's extremely disappointing that so-called consensual stop and search continues with little return other than a potential for the police to become further alienated from targeted groups.

"We believe this questionable practice should stop immediately, not least as Police Scotland's own statistics, unsurprisingly, show that detection rates are significantly higher for statutory searches.

"As the Police Authority heard only last week, some police officers still perceive that they are under pressure to meet stop and search volume targets, so it would be helpful for the new chief constable to make clear that officers should only undertake searches which have a basis in law and they should more readily utilise their greatest power: the power of discretion."