Predictors of adult spelling in an orthography of intermediate depth

What is the hallmark of a good speller? Spelling is a critical component in learning to become literate, but how it works in literate adults remains poorly explored. We examined word and pseudoword spelling in 214 adults in relation to general cognitive abilities, vocabulary, reading history, reading performance, phonological processing and rapid automatized naming. We conducted hierarchical multiple regression analyses to uncover predictors of spelling performance and compared a subsample of good and poor spellers to identify patterns of cognitive and language abilities associated with high vs. low spelling ability. In the regression model under test, which progressed from general cognitive and language abilities to specific reading-related skills, the most important predictor for word spelling was vocabulary, and for pseudoword spelling phonological processing (phoneme deletion). The model explained 20% of word spelling, and 8% of pseudoword spelling, variance. Good spellers outperformed poor spellers in reading connected text and pseudowords, and in phonological processing; poor spellers typically had a history of reading difficulties but similar levels of cognitive ability, word reading and RAN performance. Overall, our findings indicate that adult spelling relies more strongly on word knowledge than on reading proficiency and that, as in literacy acquisition, good phonology-related abilities are a hallmark of proficient adult spellers.