A systematic review of Phonological Components Analysis therapy studies for aphasia

Among the wide range of anomia treatments for persons with aphasia (PWA), Phonological Components Analysis (PCA) is a well-known alternative. A systematic review of PCA efficacy studies for PWA was conducted to extract treatment-related and participant-related characteristics, to synthesise immediate and long-term outcomes and to assess the methodological quality of PCA studies (PROSPERO pre-registration CRD42024552047). Experimental studies on adults with post-stroke aphasia focusing on the efficacy of PCA published in English were included. Studies combining PCA with other treatment approaches, involving people with neurodegenerative disorders, without efficacy measures, or in dissertations, theses, and conference papers were excluded. The EBSCOhost platform and citations of the original PCA paper were last searched in November 2024. In total, thirteen studies were selected involving 89 PWA. Participants were at least 6 months post-stroke, and 75 % of them presented with Broca's or anomic aphasia. The quality of PCA efficacy studies was relatively high according to the Single Case Experimental Design scale (mean 8.6 ± 1.0, range 7-10). Picture naming improved to reach at least a small effect size in 74 % of PWA (58/85) for trained items immediately after PCA and in 55 % of PWA (38/71) in the maintenance phase. Generalisation to untrained items occurred in 37 % of participants (22/59). Overall, PCA led to positive outcomes in the majority of PWA, which were often item-specific. As experimental designs were highly heterogeneous, further research is needed to better understand the optimal target population for PCA, the ideal dosage distribution, the key ingredients driving the improvement, and their neural correlates.