Table 1.
Description of recruitment Internet or social media platforms utilized in the study
| Platforms | Type | Description | Number of Users |
|---|---|---|---|
| FREE PLATFORMS | |||
| Tumblr | Blog | Enables sharing and reposting of content | 110M |
| Craigslist | Commercial | Displays classified advertisements | 50M |
| Facebook** | Social Media | Enables sharing of photos, videos, pages, and apps | 1.3 Bn |
| LmkedIN | Social Media | Networking business and professional | 200M |
| MySpace | Social Media | Enables sharing of photos, videos, pages, and apps | 30M |
| Social Media | Enables Micro-Hogging, RSS*, updates, following organizations and individuals | 600M | |
| 4Chan | Social Bookmarking | Enables rapid sharing of content and images | N/A |
| Blinklist | Social Bookmarking | Enables tracking, saving and sharing of website links | N/A |
| Chime.in | Social Bookmarking | Aggregates news and links | N/A |
| De.li.cious | Social Bookmarking | Enables storing, sharing, and discovering web bookmarks | 5.3M |
| Digg | Social Bookmarking | Aggregates news | N/A |
| Social Bookmarking | Enables sharing of images, website, content | 48.7M | |
| Social Bookmarking | Enables sharing of images and website and aggregating news | N/A | |
| Stumbleupon | Social Bookmarking | Enables storing, sharing, and discovering web bookmarks | N/A |
| PAID PLATFORMS | |||
| General | Enables content searching | lBn+ | |
| Findparticipants | Research Specific | Enables connecting academic researchers with research participants worldwide | N/A |
| Facebook** | Social Media | Enables sharing of photos, videos, pages, and apps | 1.3 Bn |
| Amazon Mechanical Turk | Commercial | Enables crowdsourcing of Internet marketplace and completion of tasks for a small fee | 100K |
*
Bn=Billion, M=Million, K=Thousand, N/A=not applicable, RSS=Rich Site Summary
**
Facebook was used as both a free and paid platform