Cognitive Underpinnings of Functional Reading Difficulties in Polish Adults

Background/Objectives. Low functional literacy in adulthood is a growing issue, yet the cognitive profiles of struggling adult readers in transparent orthographies remain under-researched. This study investigated the cognitive and reading-related predictors of reading comprehension in Polish adults using the Simple View of Reading framework. Methods. We analyzed data from 158 adults recruited as typical readers (TRs, n = 76) and low readers (LRs, n = 82) based on functional reading comprehension scores. Participants completed comprehensive behavioral assessments measuring decoding, listening comprehension, phonological awareness and memory (PA&M), rapid automatized naming (RAN), and language abilities. Results. Path analysis indicated that both decoding and listening comprehension independently and significantly distinguished TRs from LRs (McKelvey-Zavoina R² = 43.6%). However, multigroup analysis revealed differing mechanisms between the two groups: reading comprehension in TRs was driven primarily by listening comprehension, whereas comprehension in LRs was constrained by decoding, which was heavily influenced by RAN and PA. Furthermore, latent profile analysis uncovered significant heterogeneity among the struggling readers, identifying three distinct subgroups: a language-deficit profile (53.8%), a cognitively typical profile (37.5%), and a dyslexic profile (8.8%). These distinct subprofiles aligned with varied background factors, including self-reported dyslexia and early home literacy environment. Conclusions. This study demonstrates that functional reading difficulties in Polish adults are not homogeneous. The identification of three distinct profiles among low readers - language deficit, cognitively typical, and dyslexic - highlights that interventions must be tailored to specific cognitive needs. These findings underscore the necessity for specialized adult-literacy support in Poland to address the growing challenge of low functional literacy and its associated social and economic risks.