Before my sons started school, I learned a lesson known to nearly all parents. When children are going to spike a fever, complain of nausea, develop a weird-looking rash or come down with some sort of unusualsounding cough, they inevitably do so at approximately 5.45 p.m. on a Friday afternoon. I wouldn’t say that children actually choose this specific time to begin manifesting symptoms of some unfamiliar health problem, but in our household, at least, health concerns always seemed to arise at this time – because the pediatrician’s office closed at 5.30 p.m. The timing meant that getting a health care professional’s assessment of the problem would require a trip to either the emergency room or an urgent care center, staffed by doctors and nurses we had never met before. Visiting either of those places meant, first of all, taking a child who might already be feeling bad into an unknown environment, waiting for an hour (or more, sometimes much more) to see a doctor, and exposing both child and parent to all of the (potentially more serious) viruses other patients had brought to the waiting room. In most cases we knew that the rash, cough, fever or upset stomach would turn out to be of no great consequence anyway, but when one’s child is ill, most parents experience an intense need for reliable, trustworthy health information. How to balance that need to have questions answered and reassurance provided against the inconvenience, possible discomfort and potential for exposure to other illnesses inherent in taking the child to an urgent care center? The answer, at least some of the time, was the Internet or, as it’s sometimes called, “Dr. Google” (Fox, 2013). While we would never have

hesitated to take our boys to a health facility for an injury or a clearly serious illness, there were certainly times when it was helpful to be able to use an online site like Healthfinder.gov or the American Academy of Pediatrics’ healthychildren.org to obtain information that would help us decide whether we needed to see a doctor as soon as possible or take a wait-and-see approach. The Web today gives individuals access to a vast wealth of free health information accessible 24 hours a day from anywhere the individual can connect to the Internet. Of course, that information varies widely in terms of quality, reliability and usefulness, and some of it is far more likely to cause harm (e.g., tobacco advertising, promotions for “miracle” drugs or supplements, pro-anorexia sites) than to help individuals improve their health. However, there are also numerous sites produced by governments, health advocacy organizations, disease-specific patient communities and even corporate entities like hospitals and insurance companies that are intended to help individuals develop and maintain better health. These online health information resources differ from traditional public health campaigns in that they often cover a very wide range of topics rather than focusing on a specific issue, and may be oriented toward helping people improve their overall health rather than encouraging people to adopt one or two specific health-promoting behaviors. For that reason, online health information is categorized here as being focused primarily at the individual level and being intended to produce positive health outcomes. This chapter discusses the research on the availability, quality and use of online health information, and the impact online health information use has on individuals; it focuses on health information provided, usually by a government agency or healthrelated organization, for use by consumers seeking health information or advice. Chapter 12 addresses the impact of social media, blogs and online forums, which may have either positive or negative effects on individuals’ health knowledge, beliefs and behavior but are not necessarily intended to do so. One obvious question that is, nonetheless, nearly impossible to answer is this: How much health information is available online? Perhaps not surprisingly, there appear to be no official data on the number of organizations, groups or individuals regularly posting health information on the Web. A Google search for the term “health information” returns nearly 29 million hits, but of course, the vast majority of

people searching for health information would not use such a generic term; rather, most people seeking health information online will start with terms specific to their concern, such as “rash” or “breast cancer” or “insurance.” In terms of the professional biomedical literature – research articles published by researchers primarily for clinicians or other researchers – an assessment published in 2006 estimated that this literature, much of it fully accessible online, had grown at a “double-exponential pace” over the preceding 20 years. Hunter and Cohen (2006) calculated that MEDLINE, the database used by the National Library of Medicine’s PubMed search engine, had “grown at a ~4.2% compounded annual growth rate” (p. 589). Of the 16 million publications indexed in MEDLINE by 2005, three million had been added since 2000, with more than 1,800 publications added to the index per day in 2005 (Hunter & Cohen, 2006). By 2014, PubMed had indexed more than 24 million citations from MEDLINE, other life science journals and e-books (National Library of Medicine, n.d.). PubMed’s 24 million citations primarily reflect information intended for use by health professionals or researchers, rather than consumers, and for most individuals a consultation with “Dr. Google” will return very few links, if any, to these scholarly articles. Still, in many cases the information is available for consumers who have the confidence to attempt to understand the technical language.