ABSTRACT: Importance:As part of the Choosing Wisely campaign, primary care, surgery, and neurology societies have identified carotid imaging ordered for screening, preoperative evaluation, and syncope as frequently low value. Objective:To determine the changes in overall and indication-specific rates of carotid imaging following Choosing Wisely recommendations. Design, Setting, and Participants:This serial cross-sectional study compared annual rates of carotid imaging before Choosing Wisely recommendations (ie, 2007 to 2012) and after (ie, 2013 to 2016) among adults receiving care in the Veterans Health Administration (VHA) national health system. Data analysis was performed from April 10, 2019, to November 27, 2019. Exposures:Release of the Choosing Wisely recommendations. Main Outcomes and Measures:Annual rates of overall imaging, imaging ordered for stroke workup, imaging ordered for low-value indications (ie, screening owing to carotid bruit, preoperative evaluation, and syncope). Indications were identified using a text lexicon algorithm based on electronic health record review of a stratified random sample of 1000 free-text imaging orders. The subsequent performance of carotid procedures within 6 months after carotid imaging was assessed. Results:Between 2007 and 2016, 809?071 carotid imaging examinations were identified (mean [SD] age of patients undergoing imaging, 69 [10] years; 776?632 [96%] men), of which 201?467 images (24.9%) were ordered for low-value indications (67?064 [8.2%] for carotid bruit, 25?032 [3.1%] for preoperative evaluation, and 109?400 [13.5%] for syncope), 257?369 (31.8%) for stroke workup, and 350?235 (43.3%) for other indications. Imaging for carotid bruits declined across the study period while there was no significant change in imaging for syncope or preoperative evaluation. Compared with the 6 years before, during the 4 years following Choosing Wisely recommendations, there was no change in the trend for syncope, a small decline in preoperative imaging (post-Choosing Wisely trend, -0.1 [95% CI, -0.1 to <-0.1] images per 10?000 veterans), and a continued but less steep decline in imaging for carotid bruits (post-Choosing Wisely trend, -0.3 [95% CI, -0.3 to -0.2] images per 10?000 veterans). During the study period, 17?689 carotid procedures were identified, of which 3232 (18.3%) were preceded by carotid imaging ordered for low-value indications. Conclusions and Relevance:These findings suggest that Choosing Wisely recommendations were not associated with a meaningful change in low-value carotid imaging in a national integrated health system. To reduce low-value testing and utilization cascades, interventions targeting ordering clinicians are needed to augment the impact of public awareness campaigns.