A spotlight on preschool: the influence of family factors on children's early literacy skills.

RATIONALE: Phonological awareness, letter knowledge, oral language (including sentence recall) and rapid automatised naming are acknowledged within-child predictors of literacy development. Separate research has identified family factors including socio-economic status, parents' level of education and family history. However, both approaches have left unexplained significant amounts of variance in literacy outcomes. This longitudinal study sought to improve prospective classification accuracy for young children at risk of literacy failure by adding two new family measures (parents' phonological awareness and parents' perceived self-efficacy), and then combining the within-child and family factors. METHOD: Pre-literacy skills were measured in 102 four year olds (46 girls and 56 boys) at the beginning of Preschool, and then at the beginning and end of Kindergarten, when rapid automatised naming was also measured. Family factors data were collected at the beginning of Preschool, and children's literacy outcomes were measured at the end of Year 1 (age 6-7 years). RESULTS: Children from high-risk backgrounds showed poorer literacy outcomes than low-risk students, though three family factors (school socio-economic status, parents' phonological awareness, and family history) typically accounted for less Year 1 variance than the within-child factors. Combining these family factors with the end of Kindergarten within-child factors provided the most accurate classification (i.e., sensitivity = .85; specificity = .90; overall correct = .88). IMPLICATIONS: Our approach would identify at-risk children for intervention before they began to fail. Moreover, it would be cost-effective because although few at-risk children would be missed, allocation of unnecessary educational resources would be minimised.

Psychophysical indices of perceptual functioning in dyslexia: A psychometric analysis.

An influential causal theory attributes dyslexia to visual and/or auditory perceptual deficits. This theory derives from group differences between individuals with dyslexia and controls on a range of psychophysical tasks, but there is substantial variation, both between individuals within a group and from task to task. We addressed two questions. First, do psychophysical measures have sufficient reliability to assess perceptual deficits in individuals? Second, do different psychophysical tasks measure a common underlying construct? We studied 104 adults with a wide range of reading ability and two comparison groups of 49 dyslexic adults and 41 adults with normal reading, measuring performance on four auditory and two visual tasks. We observed moderate to high test-retest reliability for most tasks. While people with dyslexia were more likely to display poor task performance, we were unable to demonstrate either construct validity for any of the current theories of perceptual deficits or predictive validity for reading ability. We suggest that deficient perceptual task performance in dyslexia may be an associated (and inconsistent) marker of underlying neurological abnormality, rather than being causally implicated in reading difficulties.

The reliability and validity of tasks measuring perception of rapid sequences in children with dyslexia.

BACKGROUND: Claims that children with reading and oral language deficits have impaired perception of sequential sounds are usually based on psychophysical measures of auditory temporal processing (ATP) designed to characterise group performance. If we are to use these measures (e.g., the Tallal, 1980, Repetition Test) as the basis for intervention in language and literacy deficits, we need to demonstrate that they can effectively quantify individual differences. Therefore, questions of standardisation, reliability and construct validity can no longer be ignored. METHOD: We explored these issues in three studies: (i) 52 Dyslexics and Good Readers aged 8 to 11 years performed a task requiring perception of rapid sequences (PRS) based on the Tallal Repetition Test; (ii) a subgroup of the initial sample was retested on the task three to four months later, and after extended practice; (iii) a further subgroup then completed a rate of auditory processing task using a backward recognition masking paradigm. RESULTS: With a standardised methodology, we were able to replicate previous results with the PRS task, and demonstrate moderate reliability of measurement across time and practice. However, there were large effects of exposure and practice, and the task did not seem useful for identifying absolute and continuing deficits in given individuals. CONCLUSIONS: Our results call into question the use of this type of task as an individual measure of ATP. Neither is it certain that it is capturing what is currently understood as ATP.

Cost-effective prediction of reading difficulties.

This study addressed 2 questions: (a) Can preschoolers who will fail at reading be more efficiently identified by targeting those at highest risk for reading problems? and (b) will auditory temporal processing (ATP) improve the accuracy of identification derived from phonological processing and oral language ability? A sample of 227 preschoolers was screened for Performance IQ and was tested on phonological awareness (PA). The upper and lower quartiles of the PA distribution were selected as being at lowest and highest risk, respectively, for reading failure. Children with good and poor PA were tested on ATP, phonological short-term memory, rapid automatized naming, oral language, receptive vocabulary, and 2 measures of listening comprehension. Reading outcomes were measured at the end of Year 2. Only 1 child in the good-PA group became a poor reader by the end of Year 2, confirming that being in the top quartile for PA predicts positive reading outcomes. Discriminant analysis using the authors' test battery within the poor-PA group identified poor readers with sensitivity of.91 and specificity of.84, but ATP did not improve classification accuracy afforded by phonological and oral language. A brief screening procedure was formulated using only PA, phonological short-term memory, and demographic variables, with which 80% of children with poor PA who are at risk of reading problems can be identified. Further refinements of this screening procedure would increase accuracy of identification at the cost of only a small increment in required testing time.