A new study in Social Science Computer Review suggests that Reddit is a great source for recruitment of people for academic surveys. The author has posted requests for participants on a subreddit and offered no payment. A total of 962 people started the survey and 669 finished it and a final number of 526 participants were used in the analysis.
The author argues that using subreddits to recruit is a benefit for getting people interested in particular topics, and also suggests that it is great because there is no cost involved. There are limitations (self selection) and the author provides some guidelines on recruitment that arguably address this.
I’m not sure I see the value over recruiting from Craigslist, and I have to wonder if someone who loyally follows a topical subreddit is significantly different from someone in the population as a whole. But as people keep looking for new opportunities, I expect will see more studies like this in the future.