Recalled age of menarche in Britain

The purpose of this study was to determine recalled age at menarche from the National Child Development Survey of all children born in Britain in one week of 1958. All subjects were questioned at the same age (16 years); mean age at menarche was estimated as 13.3 +/- 0.02 years. The data deviate significantly from normality. Marked regional variation occurred but very little social class differentiation was apparent.