Population sex differences in IQ at Age 11:The Scottish mental survey 1932

Deary, I.J., Thorpe, G., Wilson, V., Starr, J.M. and Whalley, L.J. (2003) Population sex differences in IQ at Age 11:The Scottish mental survey 1932. Intelligence, 31(6), 533–542. (doi: 10.1016/S0160-2896(03)00053-9)

Abstract

There is uncertainty whether the sexes differ with respect to their mean levels and variabilities in mental ability test scores. Here we describe the cognitive ability distribution in 80,000+ children—almost everyone born in Scotland in 1921—tested at age 11 in 1932. There were no significant mean differences in cognitive test scores between boys and girls, but there was a highly significant difference in their standard deviations (P<.001). Boys were over-represented at the low and high extremes of cognitive ability. These findings, the first to be presented from a whole population, might in part explain such cognitive outcomes as the slight excess of men achieving first class university degrees, and the excess of males with learning difficulties.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Wilson, Dr Valerie
• Authors: Deary, I.J., Thorpe, G., Wilson, V., Starr, J.M., and Whalley, L.J.
• College/School: College of Social Sciences > School of Education
• Journal Name: Intelligence