How fluid can the cohort be?
This will to some extent depend on the circumstances of the individual school and on such factors as the outcome of any review of identification procedures, and the level of mobility in the school. We would not want membership of the cohort to be adjusted each year on the basis of entirely different identification criteria; we would expect refinement and some incomings and outgoings at the margins on top of year group changes, but for the main body of identified pupils to remain the same.
