CloudResearch allows you to use "anonymized" Worker IDs, which are MTurk Worker IDs that have been encrypted. These IDs offer workers an extra layer of privacy and assuage some IRB concerns about privacy.
On Mechanical Turk, each worker is given a unique Worker ID. CloudResearch gives researchers the option to create a "anonymized" worker ID for each participant in their study.
When you choose the Anonymize Worker IDs feature, all Worker IDs that appear in your study's downloadable .csv file will appear encrypted. For example, if the Worker ID is "ABCDEFGHJKL," it will instead appear as "TP_1UPKSI2WHSJ4." This encrypted CloudResearch Worker ID begins with the letters TP and can be used in all operations on CloudResearch where an Amazon Worker ID can be used. For example, you can use the CloudResearch ID to Include or Exclude workers from a study, add Workers to a Worker Group, or grant workers a bonus.
Anonymize Worker IDs is a Pro Feature you can select on the Pro Features page during study setup.
For more detail on the Anonymize Worker IDs feature see our blog post.