Quality and safety issues of web-based information about herbal medicines in the treatment of cancer.

A number of studies have been carried out to assess health information on the internet and they all have demonstrated that, whereas the internet can be the third opinion for many patients, often contains inaccurate and misleading information. Furthermore, as herbal medicines are increasingly used by patients, it is imperative to assess the quality of information presented on the internet. Hence, the aim of this study was to assess the quality and safety of the information presented on the internet about medicinal herbs specifically in the field of cancer. Two hundred relevant websites were initially selected from a process using 10 search engines and the keywords 'herbs' and 'cancer', and 43 sites actually met all inclusion criteria. Assessment of both quality and safety indicators was carried out using the DISCERN instrument, which has been developed to enable consumers and information providers to judge the quality of health information. Readability scores of the sites were also obtained (Flesch formula). It was shown that most sites had low quality in a number of indicators, including accuracy of information, revealing sources of information, biased presentation of information or regularity of updates. The mean score for quality was 22.12 (S.D.=4.18) out of a maximum score of 50. The mean safety score was 13.26 (S.D.=2.14) out of a maximum score of 30. Commercial sites had the most inaccurate or misleading information, emphasizing only the positive aspects of the use of herbs, with little or no evidence. The only biomedical sites assessed achieved the highest score in both quality and safety. Readability of the information was equal to the school level of college (mean=44.63). Seven percent of the sites discouraged the use of conventional medicine. Results suggest that health professionals should talk about use of alternative therapies with their patients and help them find the best available information when using the internet.