Table 2. Prevalence of Misinformation in Posts That Contained a Link to DANMASK-19 That Were Made to the Subsets of Public Facebook Groups Identified as the Most or Least Likely to Be Affected by Automation.

Facebook group typea	Total No. of posts to Facebook group typeb	Type of misinformation included in postsc
		Posts containing harm		Posts with conspiratorial claims		Posts making neither claim
		% (95% CI)d	PR (95% CI)e	% (95% CI)	PR (95% CI)	% (95% CI)	PR (95% CI)
Most affected by automation	262	19.8 (14.9-24.5)	2.3 (1.0-6.5)	50.8 (44.6-56.5)	2.5 (1.5-4.5)	43.9 (37.4-49.6)	0.6 (0.5-0.7)
Least affected by automation	59	8.5 (1.7-15.2)	NA	20.3 (10.2-30.5)	NA	72.9 (59.3-81.4)	NA

Abbreviations: DANMASK-19; Danish Study to Assess Face Masks for the Protection Against COVID-19 Infection; NA, not applicable; PR, prevalence ratio.

^aThe subsets of Facebook groups that hosted a link to the DANMASK-19 were categorized as either most or least likely to be affected by automation, which included 169 and 58 groups, respectively.

^bThe authors labeled all posts that contained a link to DANMASK-19 that were posted to public Facebook groups that were identified as most or least likely affected by automation. This column refers to the number of posts labeled in each category after any deleted posts were omitted, because the content was not available to label.

^cThese outcomes included: (1) incorrectly stating the conclusions of DANMASK-19 by claiming wearing a mask harmed the wearer (yes/no), (2) promoting conspiracies by claiming covert political/corporate control of DANMASK-19 (yes/no), and (3) making neither of the aforementioned claims (yes/no).

^dThe percentages do not sum to 100 because the categories are not mutually exclusive.

^eThe PR is the percentage of all posts made to Facebook groups that were most affected by automation divided by the percentage of all posts made to Facebook groups that were least affected by automation.