Accuracy and consistency in morphological spelling: evidence from Greek-speaking children with and without spelling difficulties

In this study, we examined the accuracy and consistency of Greek-speaking children with spelling difficulties using a spelling level-matched design at two time points. Eighty-seven children were selected for inclusion in three groups: a group with spelling difficulties (SpD, n = 22 fifth graders) and two control groups, a chronological age-matched group (CAM, n = 33 fifth graders) and a spelling age-matched group (SpAM, n = 32 third graders). They completed a spelling dictation task at Time 1 (grades 3 and 5) and nine months later at Time 2 (grades 4 and 6). The spelling task included 69 words and was designed to test the spelling of lexical, derivational, and inflectional morphemes. Participants’ spelling performance was evaluated according to three measures: spelling accuracy (SA), spelling consistency (SC) and spelling consistency in accurate spelling (SCAS). In all measures, the spelling performance of the SpD group was lower than that of the CAM group but similar to that of the SpAM group. Importantly, the SpD and SpAM groups also exhibited similar levels on the consistency measures used in this study. Derivational morphemes were spelled less accurately and less consistently than the other morpheme types, suggesting that the linguistic characteristics of the morphemes to be spelled are crucial for spelling for all children, with or without spelling difficulties.