Anyone know about InCAS tests / scores?

[takingthep]

DS1 is in a private school, they have been doing InCAS tests for several years now.

Is is correct that the standardised scores should be fairly consistent year on year for him? Is it that a falling score is indicative of a child who is not learning or being taught to the best advantage? I seem to remember the head telling us this....

So are these tests supposed to be indicative of ability - and therefor scores should remain about the same? I'm not expecting them to be identical but similar....

*therefore

My DS private school uses them and my DS has just finished yr3. Based on his results and feedback from teacher the outcome can vary hugely based on day of the week, what they had for lunch, whether they did PE before hand, whether (in DS case) he can actually be bothered to try etc... Certainly in DS case he can do astoundingly well one 1/2 term and then appallingly badly the next but the school take the results with a pinch of salt and use them as a general guide to which parts of the syllabus might need more work rather than a definitive result. They also use ePIPs tests which are a similar thing I gather...