THE Herald is to be praised for attempting to put some sort of economic context into its presentation of league tables for Scottish schools ("East Renfrewshire schools top Herald league tables", The Herald, December 19, and Letters, December 20).

However, I believe the methodology is flawed.

In setting out the performance of fifth-year pupils attaining five Highers, The Herald – and some other news organisations – used the free school meals measure as an indication of relative poverty. While it is true that this is a reasonable approach to take in terms of showing the percentage of pupils in poverty, it is inappropriate when discussing high attainment. Poverty can explain, or help to explain, low attainment among groups; high attainment is related to wealth, not inverse poverty. Although they are of course related, the measures are not opposite sides of the same coin, particularly when looking at what is a minority number of pupils in even the highest-attaining schools.

Since, by and large, the "bottom" cohort economically are not those who achieve these results, to predict the likely level of high attainment, or indeed to compare the levels among schools, wealth statistics should be used. Depending on the socio-economic mix of the catchment, often made more acute by the flight of children of wealthier parents in some socially mixed areas to schools in more affluent areas, two schools could easily have the same levels of free school meals, but widely different numbers of pupils in the upper quartile economically. It is the latter measure which will better determine attainment of five Highers.

Frank Hotchkiss,

23 Hillside, West Kilbride.