Little is known about the underlying causes and developmental patterns of stability and change in early reading abilities. In a longitudinal study of twins (n=4,291 pairs), individual differences in reading achievement assessed by teachers using U.K. National Curriculum (NC) criteria showed substantial heritabilities at ages 7, 9, and 10 years…

Many research questions require the assessment of reading in large samples of children. We compared two nonconventional procedures for early reading assessment: test administration by telephone, and teacher assessment. Five thousand five hundred and forty four children participating in a longitudinal twin study were assessed by telephone using the…