ay continue into the secondary school years. However,
we predicted that performance would be influenced both by previous
levels of written language and by concurrent language abilities, as well
as limitations in transcription skills. In addition, the relationships
between oral language and reading (Wise et al., 2007) led us to predict
that over time students' writing performance would be mediated by
their levels of reading.
To test these predictions, a cohort of adolescents that had been
identified with SLI at 8 years 3 months (and followed for the subsequent
8 years) completed a battery of language and literacy tests, cognitive
measures, and a handwriting fluency measure at age 16. We assessed
writing skill through the analytic scoring scale for the writing measure
of the Wechsler Objective Language Dimensions (WOLD; Wechsler, 1996;
Rust, 1996) and computed measures of text length given the relationships
between text length and quality for elementary school students (Gansle,
Noell, VanDerHeyden, Naquin, & Slider, 2002; Graham et al., 1997).
We predicted that limited expressive language would reduce text length
and thereby reduce the performance of older students with a history of
SLI. We used hierarchical regression and path analysis to examine the
pattern of relationships among language, literacy, and writing measures
both concurrently and over time to produce a model of the factors
supporting text production.
Following a survey of educational provision in two local education
authorities (LEAs) in the United Kingdom, our research team asked
professionals (speech and language therapists, educational
psychologists, and special educational needs coordinators) to identify
children at age 8 who had a discrepancy between their level of
functioning in the area of speech and language and that which would be
expected given the child's functioning in other areas, and who were
also experiencing significant language-based learning needs. This
process identified a total of 133 children (Dockrell & Lindsay,
2000), from which we derived a subsample from each LEA (N = 59). We
excluded children with any additional complicating factors that might
preclude the diagnosis of SLI, and included children in two regional
special schools for children with SLI in the study (N = 10).
The resulting participants (N = 69, 17 girls and 52 boys) had been
identified as having SLI at a mean age of 8 years 3 months (SD = 4
months). All participants had English as their only language and were of
white English background. Eleven percent of the total sample was
eligible for free school meals, a measure of disadvantage in England
(Strand & Lindsay, in press), comparable to the national school
average of 14.3%. All participants required special education support to
access the curriculum, and 54% had a statement of special educational
needs (SEN) under the Education Act for England 1996. The SEN, similar
to an individualized education program in the United States, specifies
the provision that must by law be made to meet the child's unique
educational needs. This status is applied to about 3% of students in the
United Kingdom, over half of whom attend mainstream schools.
Participants were assessed an additional four times as part of a
wider longitudinal government-funded study charting the educational and
social needs of children with SLI (Dockrell, Lindsay, Palikara, et al.,
2007; see Table 1 for mean age at assessment and skills assessed). The
longitudinal study also examined the students' production of
written text at age 11 (Dockrell, Lindsay, Connelly, et al., 2007), 14,
and 16--data reported here.
As Table 2 shows, at the end of formal education the students
continued to experience difficulties with oral language and literacy.
The continued specificity of their difficulty is evident from the
statistically significant differences with nonverbal ability.
We attempted to contact all participants in their final year of
compulsory education (age 16). Sixty-two students out of the original 69
agreed to complete formal assessments; 58 agreed to complete the writ