Where and why the figures differ
The information on schools and colleges in England relates only to this year's exams, but there is data on truancy and the length of the school week. The presentation differs from previous years in that truancy rates are presented in two tables - one of authorised absence and the other of unauthorised absence.
The table for Wales gives figures for unauthorised absence and all absences. Last year, the truancy tables came under fire for not giving the levels of authorised absence.
More schools are doing vocational courses but the tabled results for vocational exams taken by fifth-formers cannot easily be compared with GCSE. The tables only show the percentage of pupils achieving the vocational qualification or passing the study unit they studied in 1993-94.
The GCSE results give three measures of performance - the proportion of pupils achieving five or more A to Cs (equivalent to the O-level); the proportion gaining five or more A to Gs and the proportion gaining at least one grade A to G.
Schools tend to be judged by the proportion of pupils who succeed in gaining five or more higher-grade GCSEs.
A similar problem of comparability between vocational qualifications and more established courses exists for the post-16 age group. The English tables give the percentage of pupils gaining Advanced General National Vocational Qualifications, BTEC national certificate or diploma, or the City and Guilds diploma of vocational education at national level.
No attempt has been made to convert the vocational qualifications to a point score that can be compared with A-levels. Advanced GNVQs are broadly equivalent to two A-levels.
School performance at A-level is measured according to a points score based on: 10 points for an A; eight points for a B; six points for a C; four points for a D and and two points for an E. (AS level is worth half an A-level. ) The Welsh table provides a different comparison - it shows the number of students awarded a vocational qualification at level 3 - equivalent to two A-levels at grades A to C. The A-levels are again given on a points score.
The tables allow comparison of school sixth-forms with sixth-form colleges and further education colleges. In previous years, results from the colleges were published separately.
This year's tables also give the number of hours of lessons in a week at each school. The hours given do not include registration and lunch breaks.
The Scottish tables do not give figures on truancy. It is planned that information on attendance will be published separately later in the year. The Scottish Office does not include figures from colleges.
The final columns in the English tables give the number of pupils in a school and the number in the sixth form, plus a figure for children with special educational needs.
The number of children with special educational needs should be taken into account when exam results are assessed.
The total only refers to children with a statement of special educational needs and does not include other children who may need extra help.