Abstract
This article investigates the statistical reliability and validity of a commonly used proxy measure of children's socio‐economic status, the Family Affluence Scale (Version II). The article is based on a secondary analysis of data taken from a stratified sample of 673 children aged 9–10 years selected from 35 schools. Reliability analysis, confirmatory factor analysis and an exploratory factor analysis are used to assess the various aspects of reliability and validity of the Family Affluence Scale. The findings indicate that the scale has a number of strengths and weaknesses. Its major strengths are that it obtains direct responses from individual children and that it shows some construct validity as a measure of socio‐economic status not captured by other widely used indicators, namely: small area indices of deprivation and ‘eligibility’ for free school meals. However, its flaws include poor measurement reliability and variable construct validity. The article concludes that while the Family Affluence Scale has the potential to address many of the limitations of other proxy measures of socio‐economic status currently being used in educational research, further developmental work on the scale is required.