Scores on the Bentley Measures of Musical Ability test (BMMA) for 897 seven-or eight-year-old children were analysed with respect to a number of factors which previous research suggested might be associated with test performance. Comparisons between the 17 schools participating revealed that the same schools tended to produce either high or low scores. Further analyses revealed a significant relationship between BMMA scores and assessments of school achievement (Standard Attainment Targets - SATs). An association was also present between those schools scoring poorly on the BMMA and those containing relatively large numbers of children receiving subsidised school meals. There was also an association with age. No significant relationship was found, however, between handedness and BMMA scores. The results not only identify some specific limitations of the BMMA, but also point to more general problems in interpreting tests designed to screen for musical ability in children.