Set-For-Variability Predicts Responsiveness to Tier 2 Reading Interventions

Abstract

ABSTRACT Purpose We contrasted the responsiveness to two theoretically driven Tier 2 reading interventions. Method Participants were 273 struggling readers (Mage = 7.7 years, 53.1% female) in Grades 2 and 3 in Canada. The first intervention taught phonics plus Set-for-Variability (SfV) and the second intervention taught phonics plus morphology within a pre-post-delayed posttest cluster RCT trial. We tested six theorized hypotheses concerning individual differences in reading growth using nested random-intercept cross-lagged panel analyses. Results Analyses indicated that (a) the relationship between the processes taught in our intervention (SfV and morphology) and word reading outcomes were observed only after the intervention, (b) SfV was a significant predictor of word reading outcomes at delayed posttest, and (c) SfV was reciprocally related to irregular word reading and to WIAT Word Reading from the posttest to the delayed posttest. There were no significant associations involving morphology predictors or intervention groups and few effects involving pseudowords. Conclusion Individual differences in SfV underlie post-intervention reading gains when either phonics plus SfV or phonics plus morphology is systematically taught to struggling readers. Strategic mental flexibility in word decoding as indexed by SfV serves as an important printed word acquisition tool in the opaque orthography of English following multi-componential remedial instruction.