The general public is exposed to multiple sources of information on medicine, either through traditional mass media (e.g., television, journals, and radio) or through the Internet (e.g., blogs, Twitter, Facebook, and the many features of Web 2.0) [1,2]. The media's potential to reach large audiences gives it an important role in providing health-related information, shaping public health-related beliefs, and influencing health behaviors [3]. However, medical information published in newspapers can often be based on scant evidence because of a lack of specialized knowledge of medical journalists, criticisms of medical information in newspapers, and a lack of available time to secure strong evidence prior to copy deadlines. In addition, information from newspapers, which should be understood by the general population, is sometimes an exaggeration or overstatement.

Erectile dysfunction is defined as a consistent or recurrent inability of a man to obtain and/or maintain a penile erection sufficient for sexual activity [4]. A duration of symptoms of at least 3 months is considered acceptable to establish a diagnosis of erectile dysfunction, except in some instances of trauma or surgery [5]. Erectile dysfunction affected about 150 million men worldwide in 2000, and this number is expected to double by 2025 as a result of improved life expectancy and the age-related nature of erectile dysfunction [6]. This disorder is also associated with lower overall life satisfaction scores, mental health quality of life (QoL) scores, and vitality QoL scores [7]. Many patients look for information on erectile dysfunction from various media outlets, and commercials on treatment for erectile dysfunction have been developed. Recently, Sugita and Miyakawa [8] reported that the size of the Japanese market for counterfeit phosphodiesterase-5 inhibitors was estimated to be about 2.5 times larger than that for genuine phosphodiesterase-5 inhibitors.

The aim of the present study was to evaluate the accuracy of news information on erectile dysfunction from 10 nationwide newspapers. Our present study will add to the growing body of research documenting the nature and influence of news information on erectile dysfunction in Korea.

Today, health is one of the main topics covered by the mass media. Good health is a prime global concern, and various factors including economic development play a significant role in shaping and defining a population's perception of health [12]. In particular, men's health, including erectile dysfunction and andropause, are important matters in developing and developed countries. In Asia, the Men's Attitudes to Life Events and Sexuality (MALES) study, which studies the prevalence and treatment of erectile dysfunction in China, Japan, Korea, Malaysia, and Taiwan, reported that 6.4% of 10,934 men between 20 and 75 years of age self-reported erectile dysfunction, and 83.5% found suitable treatments in the media [13]. Tannenbaum [14], in a survey on men's health of 2,325 Canadians between 55 and 97 years of age, reported that 35.7% of men surveyed, especially those of a younger age, showed an interest in erectile dysfunction. In an epidemiological study on erectile dysfunction in Korean men, the rate of self-reported erectile dysfunction was 13.4% in 1,570 men aged 40-75 years, and the percentage of men scoring fewer than 17 points on the International Index of Erectile Function scale was 32.4%, demonstrating a high prevalence of erectile dysfunction among Korean men [15]. Thus, the prevalence of erectile dysfunction is high, particularly in developed countries like Korea.

It might be difficult for men with erectile dysfunction who are keen to receive treatment to find a urologist, schedule an interview, and finally receive medical treatment. Kang et al. [16] reported on the numbers of prescriptions written for phosphodiesterase-5 inhibitors from each department within three medical institutions in Korea. In their study, the mean rate of prescriptions for phosphodiesterase-5 inhibitors was approximately 46.4% from the urology departments, compared with 33.0% from endocrinology, 5.1% from neurology, 4.4% from cardiology, and 3.9% from family medicine, which indirectly suggests that the medical diagnosis and treatment of erectile dysfunction was relatively low in the urology departments of the three hospitals. Mass media such as newspapers and television broadcasts are alternative sources of medical and health information. With the recent introduction of medical journalists, many medical news articles have appeared in newspapers and television broadcasts and are subsequently redistributed via the Internet. Unfortunately, as shown in our present study, the accuracy of these medicine-related articles can be unreliable.

Hwang et al. [9] performed an evidence-based medical evaluation of health information from the television news. In that study, over an 8-month period, there were 85 such reports on the evening news, and 34 of them (40.0%) were found to be inaccurate or misleading. Our study also showed that 57.4% of newspaper articles contained misinformation. In particular, using inappropriate surrogate outcomes as clinical endpoints was the most frequent error. This could be attributed to the misinterpretation of results owing to inappropriate study designs, or medical researchers assuming that anatomical or physiological endpoints in their studies could be translated directly to represent clinical outcomes in patients, and the ignorance of news reporters on the medical issues they were reporting. The second most common error was exaggerated interpretations of the study results. The reason for this might be that the researchers published exaggerated results, and the news media chose to focus on this misinformation of popular interest. The frequency of errors was higher in articles from Korean sources than in articles from foreign sources. News articles from the foreign presses were re-reported by the Korean media mainly because they were easily accessible to the journalists. On the contrary, domestic sources were often more interested in publicizing study researchers and their associated hospitals, often exaggerating claims. It might be very important to consider the conventional Korean media environment. Although the level of Korean media has been increasing, it may report biased content not based on exact evidence.

Because an increasing number of medical commentaries initially reported on television news and newspapers are now available online in media such as Twitter, Facebook, and YouTube, the accuracy of primary sources (i.e., television news and newspapers) has become more crucial. Presently, the Korean Urological Association and the Korean Society for Sexual Medicine and Andrology do not use Twitter or Facebook aggressively, so as to reduce "retweeting" or "liking" misleading information and comments made by the television news or newspapers. To curtail these errors, evidence-based medical methodology must be agreed upon and practiced by all medical journalists and the news media. Doctors must first embrace evidence-based medicine during the course of their training and clinical work and publish their research findings in relevant peer-reviewed journals before making their results public. Additionally, medical journalists should spend more time studying and digesting medical-related information and receive training in evidence-based medicine. Last but not least, both the Korean Urological Association and the Korean Society for Sexual Medicine and Andrology should constantly monitor misleading medical articles and request revisions whenever necessary. It is only through these measures that the general public can be spared the negative effects of medical misinformation.

Approximately 57% of all articles on erectile dysfunction from 10 nationwide daily newspapers were found to be inaccurate on the basis of an evidence-based medicine evaluation. To this effect, urologists, the Korean Urological Association, and the Korean Society for Sexual Medicine and Andrology play a paramount role in identifying articles containing inaccurate information. In addition, medical journalists should be trained to write articles based on evidence rather than sensation.