Inaccurate statistics showing a huge fall in the number of applicants for teacher-training courses in Wales were withdrawn two days after being issued last week.
Publication of the "dodgy data" is likely to have embarrassed the Graduate Teacher Training Registry and its parent body, UCAS (the Universities and Colleges Admissions Service) at a time when teacher recruitment is under scrutiny in Wales.
Anthony McClaran, UCAS chief executive, said: "Due to a coding error, the GTTR statistics released last week are incomplete. The GTTR apologises for any confusion. The correct statistics will be issued this week."
The organisation would not elaborate on the nature of the error, but TES Cymru understands applications to the University of Wales Institute of Cardiff - the biggest teacher-training provider in Wales - were omitted from the overall results.
Sources say the incorrect figures were released despite warnings over their reliability, and that simple checks would have identified the anomaly.
According to the erroneous statistics - the first in a series of monthly reports on applications for courses starting in 2005 - only 739 people had applied for primary courses as of January 20, down from 1,445 at the same time last year. Secondary figures were also down, by more than 47 per cent, from 729 to 384.
The correct figures up to January 27, issued this week, show applications for primary courses down a fifth (rather than by 49 per cent) from 1,464 to 1,159. Secondary applications are also down, by 4.3 per cent, to 753.
Professor John Howson, of Education Data Services, said the fall in demand for primary places suggested the market was responding to the current over-supply of primary teachers in Wales. "It might put pressure on some training providers, who will have fewer candidates to choose from," he said.
The secondary figures are more worrying, because of continuing shortages in subjects like sciences, languages and Welsh, he added.
Carl Peters, chair of the Universities Council for the Education of Teachers Cymru and dean of the school of education at the University of Wales College, Newport, was suspicious of last week's figures because his primary applications were up 25 per cent.
"What is surprising is that the GTTR statisticians did not investigate such a significant downturn in applications before they published the data," he added.
Professor Howson said the "dodgy data" could have affected teacher-recruitment policy.
An Assembly government-funded review of teacher training is due to start next month. Professor Howson, who is pushing for the matter to be investigated by the GTTR board, of which he is a member, said: "I am disappointed that there was no system of checks in place to prevent inaccuracies.
"If the error had not been spotted it could have affected recruitment policy in Wales - the fall in applications for PE courses could have led to it being classed as a shortage subject."
TES Cymru has reported extensively on the plight of newly-qualified teachers who have been unable to find enough work to allow them to complete their induction year in Wales.
The General Teaching Council for Wales reported last term that only 740 of the 1,570 teachers who qualified in 2003 had completed induction by last summer. Its latest count estimates that about 100 more NQTs from the 2003 cohort had completed induction by Christmas.