ABSTRACT
One major advantage of value-added measures over threshold performance indicators (such as the percentage of pupils attaining five or more A*–C grades at GCSE) is that all students contribute to the measure, rather than just those who happen to have crossed an arbitrary threshold, which lessens the temptation for schools to focus on borderline students at the expense of those who have predicted outcomes well below or safely above the threshold. Of course, there are still technical issues unresolved at the extremes of attainment, and the risk of teachers ‘playing the system’ has not been completely removed, but, on balance, in the era of initiatives like ‘Every Child Matters’ in the UK and ‘No Child Left Behind’ in the US, value-added models take a clear step in a positive direction and UK models are being scrutinised by policy-makers in countries like Australia (Downes and Vindurampulle 2007) and Poland (Jakubowski 2008) as they prepare to develop their own metrics.
