RESUMEN
INTRODUCTION: The Institute for Quality and Efficiency in Health Care (IQWiG, Germany) has a statutory mandate to provide patients and their family members as well as the wider public with evidence-based health information (www.informedhealthonline.org). Since 2006 IQWiG has maintained the publicly available website gesundheitsinformation.de. Currently, about 80 million people live in Germany, and the majority of them have internet access. The goal of this project was to evaluate published studies examining health information seeking behaviour (who, when and how) on the internet. METHODS: A systematic search was conducted in several databases (PubMed, MEDLINE [Ovid)], PsycInfo [Ovid] und CINAHL [Ebsco]) for studies on internet searches for health information. No study type restrictions were imposed. Data were extracted from the relevant studies, and then discussed in the project group and summarised qualitatively. RESULTS: Of the 1,150 abstracts identified, 169 publications were analysed in full. 74 studies were included, most of which were surveys (n=59). The data were extracted from these studies and then summarised qualitatively to obtain an overview of the current state of research in this field. The results suggest that the group most often searching for health-related information on the internet - either on their own behalf or on behalf of others - consists of middle-aged women with a higher level of education and income. The most common reason for initiating a search for health information is a visit to the doctor, and the most common starting point is a search engine. Page layout and user-friendliness are the main criteria for assessing the credibility of websites and the information they provide. Users are more likely to trust information that is consistent with their own experiences and opinions. DISCUSSION: There is a growing trend of using the internet as a source for health information. It seems that trust in the credibility of a given website or information mostly depends on factors that are hardly related to the quality of content. This may pose a particular challenge for the creation and dissemination of evidence-based health information. Further research is required to examine the needs of the individual groups using internet-based health information.