Classification of double deficit groups across time: an analysis of group stability from kindergarten to second grade

The Double Deficit Hypothesis of dyslexia is one approach to classifying students with reading disabilities. The theory offers four distinct groups of readers: (a) average readers, (b) students with phonological deficits, (c) students with naming speed deficits, and (d) students with double deficits: those having both (b) and (c). This study examines the stability of these groups from kindergarten to second grade. An initial sample of 214 students were tested at four time points on measures of rapid automatized naming, phonological awareness, and reading. Latent transition analyses were used to examine the stability of these groups over time. These analyses indicated moderate stability from kindergarten to second grade with the probability of movement between groups being higher in kindergarten and early first grade. The groups differed in reading achievement at each testing time, with the double deficit group obtaining the lowest scores. Implications for early assessment and intervention are discussed.