CAT4 UK standardisation: levels Pre-A to G

The standardisation of CAT4 took place between September and December 2011 in England, Wales, Scotland and Northern Ireland. A national database of schools was created and schools were grouped into 10 categories – by country (Wales, Scotland and Northern Ireland) and, for England, further grouped into independent or grammar, plus five categories of school intake based on the proportion of students taking free school meals.

Schools were selected by stratified random sampling procedures within these groupings. As this was a national sample, many schools taking part in the standardisation had never used CAT4 before. For the standardisation, schools were asked to do one pre-selected CAT4 test level and were given an option to do other levels. Schools were free to choose between the paper and digital version of the test. Primary schools were asked to test all students in the year group but secondary schools had the option either to test two randomly selected teaching groups if they tested by paper, or to test the whole year group if they chose the digital option.

The numbers of students taking part in the standardisation were as follows:

These numbers were compared with the national population:

Note: Totals may not add up to 100% due to rounding

The primary school sample is slightly over-represented by students from England and under-represented by students from Scotland. The secondary school sample is over-represented by students from Wales, Scotland and Northern Ireland and under-represented by students from England. The standardisation results were therefore weighted to account for sample bias.

The numbers of students doing the paper and digital editions are given below: