title: Can consumers trust web-based information about celiac disease? Accuracy, comprehensiveness, transparency, and readability of information on the internet.
abstract: BACKGROUND
  Celiac disease is an autoimmune disease that affects approximately 1% of the US population. Disease is characterized by damage to the small intestinal lining and malabsorption of nutrients. Celiac disease is activated in genetically susceptible individuals by dietary exposure to gluten in wheat and gluten-like proteins in rye and barley. Symptoms are diverse and include gastrointestinal and extraintestinal manifestations. Treatment requires strict adherence to a gluten-free diet. The Internet is a major source of health information about celiac disease. Nonetheless, information about celiac disease that is available on various websites often is questioned by patients and other health care professionals regarding its reliability and content.
  
  
  OBJECTIVE
  To determine the accuracy, comprehensiveness, transparency, and readability of information on 100 of the most widely accessed websites that provide information on celiac disease.
  
  
  METHODS
  Using the search term celiac disease, we analyzed 100 of the top English-language websites published by academic, commercial, nonprofit, and other professional (nonacademic) sources for accuracy, comprehensiveness, transparency, and reading grade level. Each site was assessed independently by 3 reviewers. Website accuracy and comprehensiveness were probed independently using a set of objective core information about celiac disease. We used 19 general criteria to assess website transparency. Website readability was determined by the Flesch-Kincaid reading grade level. Results for each parameter were analyzed independently. In addition, we weighted and combined parameters to generate an overall score, termed website quality.
  
  
  RESULTS
  We included 98 websites in the final analysis. Of these, 47 (48%) provided specific information about celiac disease that was less than 95% accurate (ie, the predetermined cut-off considered a minimum acceptable level of accuracy). Independent of whether the information posted was accurate, 51 of 98 (52%) websites contained less than 50% of the core celiac disease information that was considered important for inclusion on websites that provide general information about celiac disease. Academic websites were significantly less transparent (P = .005) than commercial websites in attributing authorship, timeliness of information, sources of information, and other important disclosures. The type of website publisher did not predict website accuracy, comprehensiveness, or overall website quality. Only 4 of 98 (4%) websites achieved an overall quality score of 80 or above, which a priori was set as the minimum score for a website to be judged trustworthy and reliable.
  
  
  CONCLUSIONS
  The information on many websites addressing celiac disease was not sufficiently accurate, comprehensive, and transparent, or presented at an appropriate reading grade level, to be considered sufficiently trustworthy and reliable for patients, health care providers, celiac disease support groups, and the general public. This has the potential to adversely affect decision making about important aspects of celiac disease, including its appropriate and proper diagnosis, treatment, and management.
authors.affiliation: Wm. K. Warren Medical Research Center for Celiac Disease, Department of Medicine, University of California, San Diego, La Jolla, CA, United States.
authors.forename: Shawna L
authors.initials: SL
authors.lastname: McNally
authors.forename: Michael C
authors.initials: MC
authors.lastname: Donohue
authors.forename: Kimberly P
authors.initials: KP
authors.lastname: Newton
authors.forename: Sandra P
authors.initials: SP
authors.lastname: Ogletree
authors.forename: Kristen K
authors.initials: KK
authors.lastname: Conner
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Ingegneri
authors.forename: Martin F
authors.initials: MF
authors.lastname: Kagnoff
keywords: Celiac disease; health information; website accuracy; website comprehensiveness; website quality; website transparency