A major report used to justify the Assembly government's closure of dozens of small schools in rural Wales has been branded academically flawed, TES Cymru can reveal this week.
Academics from Essex University claim the research, which dealt a serious blow to campaigners' hopes when it was published last November, cannot be relied on.
Professor Ray Pahl and Dr Liz Spencer also say it is hard to put the case studies into context as many of the participating schools were anonymous.
The academics made the claims to a cross-party Assembly committee studying the closure of small schools in rural villages. Some of them have as few as eight pupils.
However, Professor David Reynolds of Plymouth University, the leading author of the report Small School Closures in Wales, this week defended his work.
"The schools were not cherry-picked by local authorities," he said. "People should look at the consistency of the evidence, which shows people supported closures - even when they had fought against them."
The Reynolds report gives case studies of teachers who went through the process and now see it as a positive experience. They say closure and amalgamation has improved standards and lifted the morale of teachers.
Professor Reynolds, who lives in Wales, has admitted more research is needed, and this week called on the Assembly government to commission a thorough study, as well as calling for national guidelines on school closures.
"If closures have to happen - and there will be more - then there should be certain entitlements across Wales," he said. "For example, local authorities should ring-fence the money saved and put it back into the education budget."
Local campaigns against the axing of around 200 rural primaries have stepped up as many schools face closure by the end of July.
Campaigns are under way across Wales to save rural communities "with the lifeblood taken out of them" by the closure of schools, post offices, pubs and petrol stations. Housing costs also mean young families are moving away.
Powys Community Schools Action Group addressed the Assembly's committee last week, claiming closures were down to a cash-saving exercise and not surplus places.
Powys local authority, where nine schools have been threatened with closure over the past year, said it is wasting money on 4,000 surplus primary places.
Professor Reynolds believes that closing very small primaries could be used to fund slightly larger schools, with greater resources and subject-specialist teachers. This has proven to be the case in Pembrokeshire, where a pound;100 million closure programme in 1996 saved cash that was pumped back into schools and pupils.
David Hawker, the new director of the department for children, education and lifelong learning, has also questioned the viability of small schools.
Speaking recently to Welsh-language magazine Golwg, he described primaries with fewer than 90 pupils as "dodgy" due to the way funding was allocated.
In nine rural Welsh counties, 53 per cent of primary schools - 394 in total - have 90 pupils or fewer and are classed as "small" and potentially unsustainable by the Audit Commission.
Ffred Ffransis, of Welsh-language society Cymdeithas yr Iaith Gymraeg, said small schools were better promoters of the native language, keeping fluency alive.
But Dr Phil Dixon, director of the Association of Teachers and Lecturers Cymru, said: "Children can't be used as a surrogate for other causes that might be important to local campaigners but which are not about education."
Campaigners claim education has been disrupted at schools which have already been waiting for years to learn their fate.
Bob Smith, a member of the Powys action group and governor of Ysgol Carno in Powys, which has been threatened with closure since 2006, said the school was in limbo but there was still hope.
But falling pupil numbers have made some schools simply untenable and expensive to run. Llangurig Primary School is based in a tiny village in Powys. Five years ago it had 18 pupils; now there are just eight, aged between four and nine.
Headteacher Ernie Jones said there were simply no children left in the area to attend the school.
Leader, page 28.