Importance: Given evidence of overdiagnosis and overtreatment of small papillary thyroid cancers (PTCs), strategies are needed to promote the consideration of less invasive treatment options for patients with low-risk PTC. Objective: To determine the association of treatment preferences and anxiety levels for PTC with the terminology used to describe the condition. Design, Setting, and Participants: This randomized crossover study involved a community sample of 550 Australian men and women 18 years or older without a history of thyroid cancer. Between March 16, 2016, and July 26, 2016, participants accessed an online study that presented 3 hypothetical but clinically realistic scenarios, each of which described PTC as papillary thyroid cancer, papillary lesion, or abnormal cells. Participants were exposed to all 3 scenarios with the different terminologies, and participants were randomized by the order (first, second, or third) in which they viewed the terminologies. Data analysis was conducted from September 1, 2016, to May 15, 2017. Main Outcomes and Measures: Treatment choice (total thyroidectomy, hemithyroidectomy, or active surveillance), diagnosis anxiety, and treatment choice anxiety. Results: Of the 550 participants who completed the online study and were included in the analysis, 279 (50.7%) were female and the mean (SD) age was 49.9 (15.2) years. A higher proportion of participants (108 [19.6%]) chose total thyroidectomy when papillary thyroid cancer was used to describe the condition compared with the percentage of participants who chose total thyroidectomy when papillary lesion (58 [10.5%]) or abnormal cells (60 [10.9%]) terminology was used. At first exposure, the papillary thyroid cancer terminology led 60 of 186 participants (32.3%) to choose surgery compared with 46 of 191 participants (24.1%) who chose surgery after being exposed to papillary lesion terminology first (risk ratio [RR], 0.73; 95% CI, 0.53-1.02) and 47 of 173 participants (27.2%) after being exposed to abnormal cells (RR, 0.82; 95% CI, 0.60-1.14) terminology first. After the first exposure, participants who viewed papillary thyroid cancer terminology reported significantly higher levels of anxiety (mean, 7.8 of 11 points) compared with those who viewed the papillary lesion (mean, 7.0 of 11 points; mean difference, -0.8; 95% CI, -1.3 to -0.3) or abnormal cells (mean, 7.3 of 11 points; mean difference, -0.5; 95% CI, -1.0 to 0.01). Overall, interest in active surveillance was high and higher levels of anxiety were reported by those who chose surgery, regardless of which terminology was viewed first (mean difference, 1.5; 95% CI, 1.0-1.9). Conclusions and Relevance: Changing the terminology of small PTCs may be one strategy to reduce patients' anxiety levels and help them consider less invasive management options. To curtail overdiagnosis and overtreatment in PTC, other strategies may include providing balanced information about the risks and advantages of alternative treatments. Trial Registration: anzctr.org.au Identifier: ACTRN12616000271404.