For all tests except CELF-3, Subgroup 4 demonstrated the poorest performance among the four DS slope subgroups. Four subgroups within our CI sample emerged: (Subgroup 1) children demonstrating age-appropriate growth in both DSF and DSB scores over time (49/110, 44.55%) (Subgroup 2) children demonstrating age appropriate growth in DSF over time but below average growth in DSB over time (23/110, 20.91%) (Subgroup 3) children demonstrating below average growth in DSF over time but age-appropriate growth in DSB over time (19/110, 17.27%) and (Subgroup 4) children demonstrating below average growth in both DSF and DSB over time (19/110, 17.27%). For DSB, the percent of the sample more than 1 SD below the norm at each age ranged from 23 to 42% (mean = 34.5%) at ages where there were at least five children. Slopes and intercepts were used as parameters in mixed-models to assess relations between STM/WM capacity change over time and S/L outcome measures including vocabulary (PPVT), open-set set spoken word recognition (PBK), and sentence perception (HINT-C).įor DSF, the percent of the sample more than 1 SD below the norm at each age ranged from 54 to 90% (mean = 66.5%). Growth curves were computed for each child, and linear functions were fit to both DSF and DSB. Repeated measure auditory digit spans were obtained from 110 children (age 3-15 years mean 7.2 years) with at least 2 years of CI use. The enormous variability observed in conventional outcome measures of S/L may reflect individual differences in STM/WM.
Short-term memory and working memory (STM/WM), as indexed by digit span forward (DSF) and digit span backward (DSB), have been shown to be strongly correlated with speech and language (S/L) outcomes. Accounting for outcome variability among pediatric cochlear implant (CI) recipients is an enduring clinical challenge.