Assessing functional communication: validation of the Italian versions of the Communication Outcome after Stroke (COAST) scales for speakers and caregivers

Valentina Bambini, Giorgio Arcara, Beatrice Aiachini, Barbara Cattani, Maria Leonilde Dichiarante, Andrea Moro, Stefano Cappa, Caterina Pistarini

Research output: Contribution to journalArticlepeer-review


Background: There is an increasing need of assessing functional communication in daily activities and the impact on the quality of life from the perspective of the major protagonists of life situations following aphasia. Several instruments are available for English. One of the most recent is the Communication Outcome after Stroke scale for patients (COAST) and caregivers (Carer COAST). These scales are comprised of two components, interactive communication skills and their impact on quality of life, assessed through 20 question items, from the point of view of patient and carer. In contrast, the number of tools available in Italian is very limited. Aims: (i) To validate the COAST and Carer COAST scales for the Italian-speaking population; (ii) to explore the applicability of the COAST scales to a wider range of people with communication problems, not limited to moderate aphasia; (iii) to explore the agreement between patient’s and carer’s perspective on communication difficulties, and the effect of severity. Methods & Procedures: The scales were translated into Italian and adapted for the sociocultural context, preserving the accessible presentation and response format. Thirty people with a history of aphasia (from mild to severe) and 28 caregivers provided usable data. The scales’ psychometric properties were measured, along with exploratory analyses on the agreement between patients and carers. Outcomes & Results: The Italian versions of the COAST scales, i.e., COAST-IT and Carer COAST-IT, showed excellent internal consistency (α = 0.94 and 0.94–0.95, respectively), good test–retest reliability (ICC = 0.85 and 0.88, respectively), and indicative evidence of construct validity as judged by the correlations with measures derived from background and current Aachener Aphasia Test (AAT) scores (r ranging from 0.32 to 0.41 and from 0.47 to 0.70, respectively). The patient and caregiver scales were strongly correlated along the score range (r = 0.70–0.72) and agreement was not influenced by aphasia severity. Conclusions: The COAST-IT and Carer COAST-IT scales are practical and reliable patient- and carer-centred measures of functional communication and its impact on the quality of life, applicable to people with communication problems of different severity. These scales fill an important gap of effectiveness indicators for speech–language assessment and therapy in Italy. More generally, the results strengthen the need of complementing traditional language assessment with functional outcome measures, and considering the perspective both of people with communication difficulties and their carers. This adaptation could pave the way for cross-national sharing of functional communication assessment instruments and comparative studies.

Original languageEnglish
Pages (from-to)1-27
Number of pages27
Publication statusAccepted/In press - Sep 15 2016


  • Aphasia
  • carers
  • functional communication
  • patient-centred outcome measure
  • quality of life

ASJC Scopus subject areas

  • Otorhinolaryngology
  • Language and Linguistics
  • Developmental and Educational Psychology
  • Linguistics and Language
  • Neurology
  • Clinical Neurology
  • LPN and LVN


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