Table 1.
Operational definition of blog credibility indicators
| Credibility indicator | Measures | Definition |
|---|---|---|
| Affiliation | Affiliation type | Whether or not the blog claimed or appeared to be affiliated with an educational or medical institution, other not-for-profit organization, government institution, other for-profit company, or unaffiliated [19]. Educational, medical, or not-for-profit affiliation was considered more credible than no affiliation or for-profit affiliation. |
| Author identificationa | Author first and last name | Whether or not at least one of the blog's authors provided his or her first and last name. Blogs that provided names were considered more credible than those that did not. |
| Author expertise | Author background disclosure | Whether or not any authors on the blog indicated having a background in the following categories: genetics, life science, technology, medicine, and/or industry. Blogs on which authors indicated relevant expertise were considered more credible than blogs on which they did not. Subcategories of expertise were not mutually exclusive. |
| Opportunity to contact | Online contact information provision | Whether or not an email address or social media profile was provided in an easily accessible location on the blog. Blogs that provided contact information were considered more credible than blogs that did not. |
| Comments allowed | Whether or not readers could leave comments on the blog. Blogs that allowed comments were considered more credible than blogs that did not. | |
| Information currencya | Posting rate | Posting rate (i.e. the number of posts per week) as calculated by the number of posts made during the study inclusion period divided by the age of the blog measured in days since the first post or days since the beginning of the inclusion period (i.e. June 15, 2007 to June 15, 2009), whichever was fewer. Blogs with a higher posting rate were considered more credible than blogs with a lower posting rate. |
| Citation of external sourcesa | Outbound links per post | Average number of outbound links (i.e. hyperlinks directed to an external website) per post. Blogs with more outbound links were considered more credible than blogs with fewer outbound links. |
a
We used a software-assisted data processing algorithm to aid in coding this item.