23 Original Article INTRODUCTION Individuals with aphasia are at a particularly high risk of limited participation in every- day life activities involving language, such as conversation. The World Health Organi- zation model defines participation as “involvement in a life situation” [1]. Participation can be characterized as the result of a complex interaction between an individual’s health condition and his/her own personal factors, as well as the environmental cir- cumstances in which her/she lives [2]. Participatwion in conversational interactions is important not only for exchanging information but also for maintaining social relation- ships, which are critical for wellness. Traditionally, standardized aphasia assessments and conversational analysis sys- tems have focused on language rules, deficits, and patterns rather than how well lan- guage communicates information to listeners. Language impairments that negatively impact communication can restrict a person’s ability to fully participate. Therefore, im- proving their ability to participate in conversation should be a primary objective of therapy [3]. To examine the impact language impairments can have on participation, many have examined the informativeness and efficiency of the discourse production of persons with aphasia [4-9]. The Correct Information Units analysis system (CIUs) was developed to evaluate the informativeness of discourse production in response to dif- ferent stimulus materials, ranging from conversational tasks to single and sequenced picture description tasks [5]. This rule-based system was created for distinguishing The informativeness of the discourse of persons with aphasia (fluent vs. non-fluent) under structured and conversational tasks was investigated. Ten individuals, five with fluent apha- sia and five with non-fluent aphasia, who had suffered a single left hemisphere stroke, par- ticipated. Structured and conversational discourse samples were analyzed using the Correct Information Units (CIUs) analysis system. Significant differences between structured and conversational tasks were observed when comparing total number of words and total num- ber of CIUs. Participants with fluent aphasia performed better than those with non-fluent aphasia during the conversational task. No differences were found between the groups for total number of words, total number of CIUs, and percentage of CIUs during structured tasks. Keywords: Aphasia, communicative effectiveness, conversation © 2017 The Korean Association of Speech- Language Pathologists This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http:// creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Received: September 30, 2016 Revision: December 17, 2016 Accepted: December 19, 2016 Correspondence: Kim C. McCullough Appalachian State University, ASU Box 32165, Boone, USA Tel: +8282626063 Fax: +8282623153 E-mail: mcculloughkc@appstate.edu Clinical Archives of Communication Disorders / Vol. 2, No. 1:23-29 / April 2017 http://e-cacd.org/ eISSN: 2508-5948 Comparison of Structured and Unstructured Discourse Tasks in Persons with Aphasia Kim C McCullough 1 *, Dee Lance 2 , Brenda L. Beverly 3 1 Department of Communication Sciences and Disorders, Appalachian State University; University of Central Arkansas, 2 Department of Communication Sciences and Disorders; 3 University of South Alabama, Speech Pathology and Audiology, USA https://doi.org/10.21849/cacd.2016.00038