18th January 2008 at 00:00
Q: The contextual value added (CVA) score of a school that was recently inspected was not great - below 100. The local authority told the school that there was no way it would get more than a satisfactory but it got a good with outstanding features.

A: And why not? I've said many times that, contrary to popular belief, CVA is not the be all and end all. It is just one of several indicators of achievement that inspectors will weigh.

In a small school, CVA may fluctuate widely from year to year and the "confidence interval" will be quite large - which means that differences will only be flagged as significant if they are very marked.

In a school where standards are very high, CVA may look relatively lacklustre because, for example, pupils who attain Level 3 at key stage 1 have little practical prospect of attaining better than Level 5.

Q: It seems these days as though the number of inspectors determines the grade a school is likely to get. If you get an inspection with just one inspector, you are likely to end up graded good or better, if you get a team of two or three then you are stuck with satisfactory at best.

A: For more than two-thirds of inspections, the number of inspectors is simply related to the size of school (number of pupils). Some schools are, however, given a "reduced tariff inspection" (RTI). These are targeted at schools that appear to be doing well, based on test scores, previous inspections and "local intelligence" of HMI.

Even with the introduction of RTI, there is no automatic correlation between the number of inspectors and the result. There have been schools with several inspectors that have been found to be outstanding and there have been schools with RTI inspections and a lone inspector that have been found to be inadequate.

Q: How can the grossly subjective views of one or two inspectors provide "evidence" for all the things that they are supposed to judge? If I was a headteacher and they gave me anything less than I was asserting in the self assessment form I'd hang the inspectors from a yardarm.

A: At risk of incurring the wrath of your yardarm, let me explain that although inspectors draw heavily on the self assessment and use it very much as their starting point, sometimes the forms are found to be inaccurate because the school is unable to substantiate its assertions.

Selwyn Ward draws on years of inspection experience. The views expressed here are his own. To ask him a question, contact him at

Selwyn regularly answers your Ofsted questions on our forums at

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