“Wikipedia’s medical content (at the end of 2013) was made up of more than 155,000 articles and 1 billion bytes of text across more than 255 languages. This content was supported by more than 950,000 references. Content was viewed more than 4.88 billion times in 2013. …The core editor community numbered less than 300 and declined over the past 5 years. The members of this community were half health care providers and 85.5% (100/117) had a university education.”

“Despite most (97%) respondents disclosed that they already had found false information in Wikipedia, recognized errors were seldomly corrected (~20%)… Students should therefore be …encouraged to contribute to the ‘perpetual beta’ improving Wikipedia’s reliability.”

“Several problems were identified with regard to depth of discussion of mechanisms and pathogenesis of diseases, as well as poor elaboration on different investigations… Wikipedia is not a reliable source of information for medical students searching for gastroenterology and hepatology articles.”

“Many publications are citing information from a tertiary source that can be edited by anyone, although permanent, evidence based sources are available. We encourage journal editors and reviewers to use caution when publishing articles that cite Wikipedia.”

“…our efforts would be best spent editing and updating Wikipedia pages.”

“The present study demonstrated that most Wikipedia articles on the 10 most costly conditions in the United States contained assertions that are inconsistent with peer-reviewed sources.”

“Medians of word count and citation density of the CAM articles were significantly lower than those in the articles of conventional medicine therapies.”

“Wikipedia is an accurate and comprehensive source of drug-related information for undergraduate medical education.”

“…studies of Wikipedia’s “quality” have looked into one or more of the following aspects: Reliability or accuracy (that is, absence of factual errors); comprehensiveness or breadth of coverage of subject matter; currency or up-to-dateness of the article contents; and readability and quality of writing style.”

“Wikipedia articles had 26%-75% of therapeutic uses and 76%-100% of adverse effects listed in the Natural Medicines Comprehensive Database and/or Natural Standard.”

„We used search engines (French pages from Bing, Google and Yahoo) to look for information using the French equivalent of three keywords epilepsy (Épilepsie); epilepsy treatment (Épilepsie traitement) and seizure (Convulsions). ... We found six French websites which were scored higher than half of the maximal value of our scoring system (≥27.5/55): www.passeportsante.net; fr.wikipedia.org; www.fondation-epilepsie.fr; www.epilepsie-france.fr; www.doctissimo.fr; www.caducee.net.“

„A questionnaire was provided to students (n 210) of the faculty of Veterinary Medicine at the Freie Universität Berlin, Germany. The experience in writing or editing of information was low (8.6% Wikipedia, 15.3% veterinary wiki systems). Male students had significantly more writing experience than females (p 0,008). In addition, students of the higher years were more experienced in writing and editing than students of the first year (7.4% in the 4(th) year).“

„The sample was calculated by simple random sampling without replacement from the active ingredients present in the Vademecum... The existence and adequacy of the terminology was observed by accessing the Spanish edition of Wikipedia. The qualitative binary variable yes/no (presence of the pharmaceutical drug, use, posology, adverse effects, adequacy) were described by frequency and percentage, quantitative (number of queries, update) using mean and standard deviation. Of the sample studied (n 386), 171 terms were found, with 15 being adequate. Significant differences were observed between adequacy and dose (P<.001) and adverse effects (P<.001), but not with use (P .193). CONCLUSIONS: Pharmaceutical preparation entries in the Spanish edition of Wikipedia are still insufficient and the adequacy of the information remains inconsistent.“

„Web 2.0 and appropriate algorithms enable users to rely on the guidance or behavior of their peers in selecting and consuming information.“

„The International Statistical Classification of Diseases andRelated problems, 10th Edition (ICD-10) diagnostic codes for nephrology (N00–N29.8) were used as a topic list to investigate the English Wikipedia database. Comprehensiveness was assessed by the proportion of ICD-10 codes that had corresponding articles. Reliability was measured by both the number of references per article and proportion of references from substantiated sources. Finally, readability was assessed using three validated indices (Flesch-Kincaid grade level, Automated readability index, and Flesch reading ease). Nephrology articles on Wikipedia were relatively comprehensive, with 70.5% of ICD-10 codes being represented. The articles were fairly reliable,with 7.1 ± 9.8 (mean ± SD) references per article, of which 59.7 ± 35.0% were substantiated references. Finally, all three readability indices determined that nephrology articles are written at a college level.“

„25 relevant websites were evaluated using the DISCERN instrument. The highest score achieved by one of the websites was 64 of 80 and the lowest score achieved was 21 of 80. The websites achieving maximum and minimum score were Wikipedia and qualitydentistry.com, respectively.“

„46 students in a university course edited Wikipedia to enhance public access to important discoveries in chronobiology. Students worked for an average of 9 h each to evaluate the primary literature and available Wikipedia information, nominated sites for editing, and, after voting, edited the 15 Wikipedia pages they determined to be highest priorities. This assignment [1] was easy to implement, required relatively short time commitments from the professor and students, and had measurable impacts on Wikipedia and the students. Students created 3 new Wikipedia sites, edited 12 additional sites, and cited 347 peer-reviewed articles. The targeted sites all became top hits in online search engines. Because their writing was and will be read by a worldwide audience, students found the experience rewarding.“

„A Google keyword search was performed for 10 common otolaryngology problems including ear infection, hearing loss, tonsillitis, and so on. The top 10 search results for each were critically examined using the 16-item (1-5 scale) standardized DISCERN instrument. Searches for more typically chronic otolaryngic problems (eg, tinnitus, sleep apnea, etc) resulted in more biased, advertisement-type results than those for typically acute problems (eg, ear infection, sinus infection, P .03). Results from major comprehensive Web sites (WebMD, EMedicinehealth.com, Wikipedia, etc.) scored higher than other Web sites (mean DISCERN score 3.46 vs 2.48, P < .001).“

„Content on 10 mental health-related topics was extracted from 14 frequently accessed websites (including Wikipedia) providing information about depression and schizophrenia, Encyclopaedia Britannica, and a psychiatry textbook. The content was rated by experts according to the following criteria: accuracy, up-to-dateness, breadth of coverage, referencing and readability. RESULTS: Ratings varied significantly between resources according to topic. Across all topics, Wikipedia was the most highly rated in all domains except readability.“

„Twenty-four diagnoses in pediatric otolaryngology were entered in Google and the top five URLs for each were ranked. ... Wikipedia, eMedicine, and NLM/NIH MedlinePlus were the most referenced sources. For content accuracy, eMedicine [5] scored highest (84%; p<0.05) over MedlinePlus [6] (49%) and Wikipedia (46%). The highest incidence of errors and omissions per article was found in Wikipedia (0.98±0.19), twice more than eMedicine (0.42±0.19; p<0.05). Errors were similar between MedlinePlus and both eMedicine and Wikipedia. On ratings for user interface, which incorporated Flesch-Kinkaid Reading Level and Flesch Reading Ease, MedlinePlus was the most user-friendly (4.3±0.29). This was nearly twice that of eMedicine (2.4±0.26) and slightly greater than Wikipedia (3.7±0.3). All differences were significant (p<0.05). CONCLUSIONS: eMedicine has the most accurate, comprehensive content and fewest errors, but is more challenging to read and navigate. Both Wikipedia and MedlinePlus have lower content accuracy and more errors, however MedlinePlus is simplest of all to read, at a 9th Grade level.“

„Adoption studies of social media use by clinicians were systematically reviewed, up to July 26th, 2011, to determine the extent of adoption and highlight trends in institutional responses. This search led to 370 articles, of which 50 were selected for review, including 15 adoption surveys. The definition of social media is evolving rapidly; the authors define it broadly to include social networks and group-curated reference sites such as Wikipedia. Facebook accounts are very common among health science students (64-96%) and less so for professional clinicians (13-47%). Adoption rates have increased sharply in the past 4 years. Wikipedia is widely used as a reference tool.“

„A 10% sample of health related Wikipedia entries were evaluated, with a total of 2598 references assessed. In total 1473 (56%) of the references citied on the Wikipedia pages reviewed could be argued to come from clearly identifiable reputable sources. This translates to a mean number of reputable sources of 29 per Wikipedia entry. The quality of the evidence taken obtained from the 2500 plus references from over 50 Wikipedia pages was of sufficiently sound quality to suggest that, for health related entries, Wikipedia is appropriate for use by nursing students.“

„Though it is impossible to guarantee the validity of every Wikipedia article, as no one person is ultimately responsible for the content, the development of an elaborate antivandalism system explains the paradox of how quality can be sustained in a radically open editing system.“

„The five statins selected were those listed in the “Because the entries on the five most commonly prescribed statins lacked important information, the authors recommend that consumers should seek other sources and not rely solely on Wikipedia.“

„Wikipedia articles for the 20 most frequently prescribed drugs per published lists of top 200 brand and generic drugs were evaluated. Categories most frequently absent were drug interactions and medication use in breastfeeding. No article contained all categories of information. Information on contraindications and precautions, drug absorption, and adverse drug events was most frequently found to be inaccurate; descriptions of off-label indications, contraindications and precautions, drug interactions, adverse drug events, and dosing were most frequently incomplete. Referencing was poor across all articles... Conclusion: Wikipedia does not provide consistently accurate, complete, and referenced medication information.“

„To investigate the sources of online information about prescription drugs... About three quarters of the first result on Google USA for both brand and generic names linked to the National Library of Medicine. In contrast, Wikipedia was the first result for approximately 80% of generic name searches on the other 3 sites (Bing, Google Canada, and Yahoo). On these other sites, over two thirds of brand name searches led to industry-sponsored sites. The Wikipedia pages with the highest number of hits were mainly for opiates, benzodiazepines, antibiotics, and antidepressants.“

„Accessibility is one of six quality criteria articulated by the European Commission in its code of conduct for health websites. The names of 22 health conditions were entered into five search engines, and the readability of the first 10 results for each search were evaluated using Gunning FOG, SMOG, Flesch-Kincaid and Flesch Reading Ease tests (n 352). The mean reading grade was 12.30, andthe mean FRE was 46.08, scores considered 'difficult'. Websites with .gov and .nhs TLDs were the most readable while .edu sites were the least. Within texts, a trend of increasing difficulty was found with concluding paragraphs being the hardest to read. It was also found that some of the most frequent search results (such as Wikipedia pages) were amongst the hardest to read.“

„The evidence suggests that Wikipedia can have legitimate educational uses for individuals. These include a quick resource for finding general information and as an instrument for preliminary literature searching.1 The uncertain providence of information on Wikipedia should remind doctors to exercise caution when receiving established ‘fact’ from any source, whether online, published, or spoken by a senior colleague. If medical professionals can be encouraged to actively engage with Wikipedia, they may become involved in correcting errors as they are identified. Wikipedia is a rare opportunity for doctors to interact with an educational resource while helping develop an important public health information tool.“

„In this study, the coverage, accuracy, and readability of cancer information on Wikipedia were compared with those of the patient-orientated National Cancer Institute's Physician Data Query (PDQ) comprehensive cancer database. For each of 10 cancer types, medically trained personnel scored PDQ and Wikipedia articles for accuracy and presentation of controversies by using an appraisal form. ... For both Web sites, inaccuracies were rare, less than 2% of information examined. PDQ was significantly more readable than Wikipedia: Flesch-Kincaid grade level 9.6 versus 14.1. There was no difference in depth of coverage between PDQ and Wikipedia (29.9, 34.2, respectively; maximum possible score 72). Controversial aspects of cancer care were relatively poorly discussed in both resources (2.9 and 6.1 for PDQ and Wikipedia, respectively, NS; maximum possible score 18). A planned subanalysis comparing common and uncommon cancers demonstrated no difference.“

„Wikipedia.org proved significantly harder to comprehend than all other sources.“

„We have evaluated pathology informatics content in Wikipedia. Evaluation of articles on a five-point Likert scale showed high scores for comprehensiveness (4.05), quality (4.08), currency (4.18), and utility for the beginner (3.85) and advanced (3.93) learners. These results are compelling and support the thesis that Wikipedia articles can be used as the foundation for a basic curriculum in pathology informatics.“

„Three independent observers tested the English version of Wikipedia, as well as the patient version and the health professional version of the US National Cancer Institute (NCI) website. Answers were verified with authoritative resources and international guidelines. The results of our study demonstrate that the quality of osteosarcoma-related information found in the English Wikipedia is good but inferior to the patient information provided by the NCI.“

„The aim of this study was to assess the scientific quality of the 265 dental articles that were present in January 2008 in the German-language version of Wikipedia. Of the 261 usable articles, 28% were qualitatively comparable to a textbook, while 56% had partial textbook quality. About 16% of the articles fell into the third group.“

„Quality of content modules about age-related macular degeneration (AMD) was analyzed on 20 web sites. Content analysis covered 72 criteria in 11 groups. On average, 25.6% (+/-15.6) of the criteria were fulfilled. In the categories diagnostic procedures, therapy, preventive checkups, prevention and prognosis of AMD, only 12.7, 18.3, 20.0, 25.0 and 30.0%, respectively, of the required content was given.“

„For some areas of health information, Wikipedia can provide well-referenced articles.“

„Of concern, only 28% (29/105) of the respondents who reported using Wikipedia to obtain drug information were familiar with who edits and manages the Web site. This study is limited by a low response rate...“

„This study examines Web 2.0 use by 35 junior physicians in clinical settings, Diaries and interviews encompassing 177 days of internet use or 444 search incidents, analyzed via thematic analysis. Results indicate that 53% of internet visits employed user-generated or Web 2.0 content, with Google and Wikipedia used by 80% and 70% of physicians, respectively.“

„Based on its search engine ranking and page view statistics, the English Wikipedia is a prominent source of online health information compared to the other online health information providers studied.“

„Blinded to the information resources, medical academics compared conjunctivitis, multiple sclerosis and otitis media entries from Wikipedia against those from Emedicine [13] and two subscription-based resources, namely AccessMedicine [14] and UpToDate [15], using a scale developed to rank their accuracy, coverage, concision, currency and suitability for medical students. Medical librarians assessed their accessibility and usability. RESULTS: The entries in Wikipedia, in comparison with the other resources, were easy to access, navigate and well presented. Although reasonably concise and current, they failed to cover key aspects of two of the topics, and contained some factual errors. Wikipedia was thus judged unsuitable for medical students.“

„To compare the scope, completeness, and accuracy of drug information in Wikipedia with that of a free, online, traditionally edited database (Medscape Drug Reference MDR). RESULTS: Wikipedia was able to answer significantly fewer drug information questions (40.0%) compared with MDR (82.5%; p < 0.001). Wikipedia performed poorly regarding information on dosing, with a score of 0% versus the MDR score of 90.0%. Answers found in Wikipedia were 76.0% complete, while MDR provided answers that were 95.5% complete; overall, Wikipedia answers were less complete than those in Medscape (p < 0.001). No factual errors were found in Wikipedia, whereas 4 answers in Medscape conflicted with the answer key; errors of omission were higher in Wikipedia (n 48) than in MDR (n 14). There was a marked improvement in Wikipedia over time, as current entries were superior to those 90 days prior (p 0.024). CONCLUSIONS: Wikipedia has a more narrow scope, is less complete, and has more errors of omission than the comparator database.“

„Of the 203 total first generation ICD-10 diagnostic codes in gastroenterology, 168 (82.8%) had Wikipedia entries, either as articles, or as sections of an article... The average number of references per article was 6.8. The median Flesch-Kincaid grade level for these articles was 13.7, and the average Flesch reading ease score was 32.1. Conclusions: Wikipedia's content in gastroenterology is comprehensive, with over 80% of ICD-10 and ICD-9 codes represented. The reliability of the material contained therein is moderate, with more than half of gastroenterology articles being substantiated with a peer-reviewed reference. The gastroenterology articles in Wikipedia are readible with a grade level of slightly higher than high school.“

„Apomediation is a new socio-technological term that was coined to avoid the term “Web 2.0”... an information seeking strategy where people rely less on traditional experts and authorities as gatekeepers, but instead receive “guidance” from apomediaries, ie, networked collaborative filtering processes.“

„This study randomly assigned 89 medical student volunteers to use either Google or any other web-based resource (excluding Google) to research 10 advanced medical questions in a multiple choice exam. Primary outcome measures were resource efficiency (inversely related to number of links used to identify the correct answer for each question) and correctness (number of correct answers/total number of questions answered). For Google searches, the sites providing the information in question were also evaluated. RESULTS: The most frequently selected non-Google resources were Yahoo (n 531), Ask.com (n 110), and the interactive encyclopedia Wikipedia.com (n 74). Google was more efficient than all other resources (1.50 vs. 1.94 mean links, P<.0001), with no significant difference in correctness (97% [756/780] vs. 96% [747/780], P .16). After a Google search, the four most common categories of sites that provided the correct answer were dictionary/encyclopedia sites, medical websites, National Library of Medicine resources, or journal websites. Yahoo was less efficient than Google (1.90 vs. 1.54 mean links, P<.0001). However, non-Google search engines were more efficient than web sites (eg, Wikipedia, medical websites) and PubMed (1.87 vs. 2.54 mean links, P .0004).“

„22 senior students of health sciences and education evaluated the websites of Wikipedia and two major German statutory health insurances for content and presentation of patient information, one topic each. All these websites failed to meet relevant criteria, and key information such as the presentation of probabilities of success on patient-relevant outcomes, probabilities of unwanted effects, and unbiased risk communication was missing. ... In addition, the Wikipedia information tended to achieve lower comprehensibility.“

„An internet search (on Google and Yahoo) was conducted using the search terms ‘child development’, ‘parenting’, and ‘developmental milestones’. Forty-four relevant websites were identified for further analysis. The average score for accuracy was 6.6 out of 10 (Wikipedia:8).“

„...results show an increasing use of structured citation markup and good agreement with citation patterns seen in the scientific literature though with a slight tendency to cite articles in high–impact journals such as Nature and Science.“

„Peer reviewers recruited by Nature identified an average of four inaccuracies in the Wikipedia articles they examined and an average of around three in articles on the same topics in Britannica.“