Firstly, as an ex teacher, I think that using the SATS as an indicator of GCSEs is questionable, but I have not looked into the stats.
My question is this.... if a child gets 100% in their SATS do they get predicted 8s and 9s at GCSE, or does it not work like that?
Is it a prediction for all GCSEs, or just maths and english because that is what the SATS test?