The current state of research of word-of-mouth in the health care sector

Health information plays a significant role in the health behavior of individuals. Word-of-mouth (WOM) is essential in this context. In recent years, new forms of online communication have greatly expanded the possibilities for seeking information and, in consequence, significantly changed communication behavior. Similarly, the doctor-patient relationship has gradually evolved and the traditional asymmetry of medical knowledge is increasingly being corrected as today’s health care consumers are becoming more well-informed. A key source of information is either in-person or online WOM. A research gap exists in terms of analyzing the current state of research of WOM in health care. Although various studies highlight the influence of WOM on health behavior, to the best of our knowledge there exists no systematic literature review that summarizes the current state of research on WOM in health care. Therefore, this paper presents a comprehensive systematic literature review on WOM in health care. The literature review investigates existing WOM studies in the health care sector based on a systematic search for articles in a twenty-year timeframe from January 2000 to December 2019. The resulting total of 34 articles constitutes the basis of this paper. These studies are analyzed using a model of WOM in health care and – based on the theory of cognitive dissonance, the theory of the strength of weak ties, and the theory of perceived risk – clustered into the creation, spread, and impact of WOM. The investigated studies emphasize the importance of the staff in the service process. Furthermore, negative reviews have a stronger impact than positive ones, with service quality representing the main reason for negative WOM. In addition, the importance of electronic word-of-mouth (eWOM) is underlined, as online reviews are gaining popularity for patient decision-making processes. Although some studies have addressed WOM in health care, research gaps remain. For example, there are few studies on eWOM and some medical disciplines in private practice are neglected in WOM research. By systematically presenting and analyzing the literature on WOM in health care, this paper represents an important starting point for future research and also provides insights into the role of WOM in health care practice.