Original post can be seen here: https://www.bbc.com/news/uk-wales-politics-60028468
UBI is where a government pays all individuals a set salary, regardless of their means.
The Welsh government plans a three-year pilot this April with about 250 care leavers, but a Senedd committee said the scheme would provide only “limited information” on the UBI concept.
The Welsh government said the scheme would provide “valuable information”.
The UBI idea, where individuals are paid a regular sum of money, has sparked debate across the world.
Advocates say a basic income could help reduce poverty, and could be easier and less stressful to navigate than more complex means-tested benefits.
Opponents say it would be extremely costly, and is not targeted at those who need it.
The Welsh proposal for a pilot, in choosing to focus on a specific group, has been criticised for not being universal.
Information on how the pilot will work has so far been limited, but the Welsh Parliament’s petitions committee report, which is not produced by ministers but a body of the Senedd, outlines some details.
It says the project would involve 250 care leavers, planned to run for about three years, and be “pitched at the living wage”.
The committee’s inquiry was prompted by a petition signed by 1,051 people, calling for a geography-based UBI.
Members of the Senedd on the committee, which includes two from Labour, one Plaid and one Conservative, said a larger group would provide more “robust results.”
“A basic income pilot for care leavers – as currently proposed by the Welsh government – will provide valuable feedback on the potential of such a scheme to improve the support to a group which faces significant challenges,” the committee said.
“However, a three-year pilot of only 250 people will offer limited information. And applying a basic income only to care leavers, will tell us little about universal basic income.”
It said payments should be guaranteed, unconditional and paid to the individual.
Benefits are not devolved in Wales and the UK government has opposed the UBI concept.
The report said the pilot will “be richer and produce more robust evidence if all relevant agencies are engaged in the enterprise”.
“The Welsh government should make every effort to persuade UK government departments to support the widest possible pilot scheme,” it said.
The report warned the project would be undermined “if participants lost entitlements they currently claim as a direct result of a failure to communicate” between the UK and Welsh governments.
Implementing UBI in Wales would be “far easier” if welfare was devolved, the committee argued.
Committee chairman Jack Sargeant said: “The Welsh government should investigate increasing the number of proposed recipients and include care leavers from as diverse as possible a range of backgrounds, locations, and circumstances to give us the evidence we need to properly evaluate this scheme.
“While not all members of the committee support UBI, we all believe that a wider pilot scheme has the potential to produce richer, more persuasive evidence for the Welsh government to consider.”
He added the evidence “may prove that UBI is an inefficient way to target those in the greatest need – or it may prove my own view that the benefits attributed to other experiments, in terms of wellbeing and economic outcomes, are achievable here in Wales”.
Swansea, Rhondda Cynon Taf and Gwynedd have called for pilots to take place in their areas.
Experiments have been held in Finland with 2,000 people who were paid €560 (£467).
The Senedd report says recipients were found to be “more satisfied with their lives and experience less mental strain”.
A Welsh government spokesman said: “The provision of a basic income to young people leaving our care system should help to reduce the challenges care leavers face. In addition, evaluation of the pilot scheme will provide valuable information about how a basic income could apply more widely.
“The minister will make a statement in the coming weeks to provide an update on the pilot.”