384 IEEE TRANSACTIONS ON PROFESSIONAL COMMUNICATION, VOL. 60, NO. 4, DECEMBER 2017 Integrative Literature Review Use of Plain-Language Guidelines to Promote Health Literacy MARGARET GRENE ,YVONNE CLEARY , AND ANN MARCUS-QUINN Abstract—Research problem: Studies by the American Institute of Medicine and the European Health Literacy Survey describe considerable levels of either inadequate or problematic health literacy. This health literacy problem is intensified when frontline healthcare practitioners must rely on printed education materials to compensate for the lack of time to instruct patients about their health management. Applying plain-language guidelines to health promotion materials may increase their effectiveness, particularly for patients with low health literacy. Research questions: 1. In what ways have plain-language guidelines been applied in health information materials for patients with varying degrees of health literacy, according to recent studies? 2. Have studies found that materials that apply plain-language guidelines are effective in health information promotion? Methodology: This article presents the findings from an integrative literature review of research into the use of plain language to promote health literacy. The systematic review identified scholarly, evidence-based studies that included reference to the use of plain-language guidelines. This article describes the detailed selection process and characterizes the corpus of articles along four dimensions: objectives, methodology, plain-language guidelines used, and findings. Results and conclusions: The review identified 13 articles that explored the use of plain-language guidelines in health literacy promotion. Analysis of these articles demonstrates that plain-language guidelines could play a strategic role in educating patients. Use of plain language could help healthcare practitioners to communicate critical and sometimes very complex health information effectively. Index Terms—Communication, guidelines, health literacy, plain language. At its most fundamental level, health literacy refers to the individual’s ability to understand health information as a patient in the healthcare setting, and to act on this information. The term “health literacy” was introduced in the 1970s [1], and the concept, closely linked to empowerment [2], [3], was originally used in the US and Canada. It is now being used internationally in healthcare and public-health contexts [4]. At a theoretical level, the definition of health literacy has evolved from an emphasis on the ability to handle words and numbers in a medical context to the simultaneous use of a more complex set of abilities, such as reading and acting upon written health information, or communicating needs to health professionals [5], [6]. Nutbeam [4] distinguished among three classifications of health literacy. Manuscript received January 9, 2017; revised August 14, 2017; accepted August 14, 2017. Date of current version November 22, 2017. (Corresponding author: Margaret Grene.) The authors are with the Department of Technical Communication, University of Limerick, Limerick V94 T9PX, Ireland (email: Margaret.Grene@ul.ie; Yvonne.Cleary@ul.ie; Ann.Marcus.Quinn@ul.ie). IEEE 10.1109/TPC.2017.2761578 1. Functional health literacy—The basic skills in reading and writing needed to function effectively in everyday situations. 2. Interactive health literacy—The basic skills in reading and writing needed to function effectively in everyday situations, plus more advanced cognitive and literacy skills used to extract information and derive meaning from different forms of communication, and apply this information to changing circumstances. 3. Critical health literacy—More advanced cognitive skills that can be applied to critically analyze information and use this information to exert greater control over life events and situations. In addition, Zarcadoolas et al. [7] argued that health literacy differs from general literacy because it involves the simultaneous ability to read, to understand health instructions, and to communicate medical information. Baker [8] proposed four domains of health literacy: cultural and conceptual knowledge, oral literacy, numeracy, and the ability to read and understand written medication information. Sørensen et al. [5] conducted a systematic review to distil a comprehensive definition of health literacy encompassing 17 definitions identified in the literature. Content analysis of the 17 definitions 0361-1434 C  2017 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission. See http://www.ieee.org/publications standards/publications/rights/index.html for more information.