TECHNICAL ANNEX

This Annex describes the methods that have been used to construct the value added measure for the schools that volunteered to participate in the 2002 value added pilot.

Pupils included

The KS1 - KS2 VA measure is based on the results achieved by pupils:

• who were eligible for KS2 assessment in 2002; and
• who were on roll at the time of the KS2 tests in May 2002; and
• for whom we have been able to match prior attainment in KS1 tests.

Allocation of points

The 'input' and 'output' measures for the value added calculation are based on the points awarded to pupils' results. The following tables show how points are allocated to pupils' KS1 and KS2 results.

KS1 Point Scores for reading task and reading test levels

KS1 Point Scores for all subjects except reading

KS2 Point Scores for all subjects

All pupils for whom all results are disregarded at Key Stage 1 have been excluded from the value added calculations, with one exception: if a pupil is disapplied in at least one subject and achieved at least one KS2 result which was not disregarded, then he/she will be included in the calculation with an input score of zero.

The input measure for each pupil is calculated as the average point score achieved in the reading, writing, spelling and mathematics KS1 task/test. However, before an average point score can be calculated, an overall reading level score needs to be determined from the levels achieved in the reading test and/or the reading comprehension task.

Overall Reading Level

To calculate the overall reading level the following rules are applied:

• If the pupil has achieved a level of 3 or higher in the reading comprehension test, this is the score that will be used as the overall reading level.
• If the pupil has achieved less than a Level 3 in the reading comprehension test or was not entered for the test, the level achieved in the reading task will be used as the overall reading level.

Please see example below

Example 1:

KS1 Average Point Score (APS)

The input measure for each pupil is the average (arithmetic mean) point score achieved in the reading, writing, spelling and mathematics tests at KS1, using the points allocated to each level as described earlier.

Please see example below

Example 2:

The output measure for each pupil is the average (arithmetic mean) point score achieved in the English, mathematics and science KS2 tests, using the points allocated to each level as described earlier.

Please see example below.

Example 3:

Only the pupils for whom we have identified both prior KS1 and 2002 KS2 test results in at least one subject have been included in the calculation of the value added measure. Where, in one or two subjects, the test result is missing or disregarded, the average point score is based on the remaining subject(s).

A pupil's KS1- KS2 VA score is calculated as the difference, positive (+) or negative (-), between their average KS2 point score and the median average KS2 point score for all pupils nationally with the same or similar average KS1 point score. The median is the middle value - with half of the pupils having an average KS2 point score at or below the median, and half at or above the median.

During investigations into the VA measures to be published in this pilot, it was concluded that special schools should be treated separately from mainstream schools for the purpose of calculating VA measures. The graphs below give the pattern of median KS2 average point scores across the range of average KS1 point scores for all pupils nationally in mainstream and special schools - joining the medians gives the 'national median line'.

As the graphs show, pupils at the highest extremes of KS1 achievement, i.e. with an average KS1 point score of 21 or more for mainstream schools and 11 or more for special schools have been grouped together. This has been done to ensure there are adequate numbers of pupils from which to calculate a robust median.

The median KS2 point scores are also given in the tables below:

Mainstream Schools

Special Schools

In the following example, school A has 4 pupils eligible for inclusion in the value added pilot with KS1 and KS2 point scores shown. The median average point scores have been allocated according to the national median line for mainstream schools shown above, and a value added score calculated for each pupil.

A school's VA score is a simple average (arithmetic mean) of the value added measures for all pupils in the school.

Total of all pupils' value added scores = +1

Average value added score per pupil = +1 divided by 4 (number of pupils)

Schools value added score = 0.25

The value added measure (KS1 to KS2)

The value added score for each school has been published in terms of a measure centred around 100 - i.e. by adding 100 to a school's value added score. In the example above the value added measure for school A is:

      = 0.25 + 100 = 100.25
      = 100.3 (rounded to one decimal place using normal rounding conventions)

Band

The pilot offers an important opportunity to explore further presentational options, which might be used in performance tables. This pilot study has been used to evaluate the possibility of publishing a 'band' alongside the VA measure. The bands use letters A-E indicating whether a school fell in the top 5% of schools nationally, the next 20%, the middle 50%, the lower 20%, or the bottom 5%.

The cut-offs for the bands used for all schools in this pilot are shown in the table below and relate to a school's value added measure, e.g. a value added measure of 100.3 would place a school in band C.

Calculation of a school's coverage indicator

This shows the percentage of pupils eligible for KS2 assessment in 2002 who were included in the value added measure for that school.

For example if a school had 30 pupils eligible for KS2 assessment in 2002 but only 25 were included in the value added calculations, the coverage indicator for that school would be:

Calculation of a school's stability indicator

This shows the percentage of pupils that have remained in a school between KS1 and KS2. It is calculated by dividing the number of pupils who took both their KS1 and KS2 tests in the school by the total number of pupils included in the value added calculation.

For example if a school had 10 pupils included in the value added calculation and only 7 took both their KS1 and KS2 tests in the same school then the stability indicator would be:

If a school does not have an infant department i.e. has a lowest age of 7 or higher, the school will be exempt from the stability indicator. These schools are shown in the tables as N/A.