Introduction: Reliable and accurate Web-based health information is extremely valuable when applied to emergency medical diagnoses. With this update we seek to build upon on the 2004 study by determining whether the completeness and accuracy of emergency medical information available online has improved over time.

Methods: The top 15 healthcare information sites, as determined by internet traffic, were reviewed between February 4, 2008, and February 29, 2008. Standard checklists were created from information provided by American Stroke Association, American Heart Association, National Institutes of Health, and American College of Emergency Physicians to evaluate medical content on each of the Web sites for 4 common emergency department diagnoses: myocardial infarct, stroke, influenza, and febrile child. Each Web site was evaluated for descriptive information, completeness, and accuracy. Data were sorted for total medical checklist items, certification and credentialing, and medical items by topic.

Results: Three of the 15 sites were excluded because of a lack of medical information on the selected topics. Completeness of sites ranged from 46% to 80% of total checklist items found. The median percentage of items found was 72. Two sites, MSN Health and Yahoo!Health, contained the greatest amount of medical information, with 98 of 123 checklist items found for each site. All Web sites but 1, Healthology.com, contained greater than 50% of aggregated checklist items, and the majority (ie, 7 of 12) contained greater than 70%. Healthology.com was the least complete Web site, containing 57 of 123 items. No significant correlation was found between credentialing and completeness of site (correlation coefficient = -0.385) or credentialing and site popularity (correlation coefficient = 0.184).

Conclusion: This study indicates that the completeness and accuracy of online emergency medical information available to the general public has improved over the past 6 years. Overall, health Web sites studied contained greater than 70% of aggregated medical information on 4 common emergency department diagnoses, and 4 sites examined advanced from 2002 to 2008. [West J Emerg Med. 2011;12(4):448–454.]