Comparison of Payment Changes and Choosing Wisely Recommendations for Use of Low-Value Laboratory Tests in the United States and Canada.

Importance: Evidence comparing the consequences of Choosing Wisely recommendations across health systems or with the consequences of recommendations plus policy change is lacking. Objectives: To compare changes in the use of 2 low-value laboratory tests after the release of Choosing Wisely recommendations across 3 health care jurisdictions and changes associated with a related policy change. Design, Setting, and Participants: This cross-sectional study was a population-based interrupted time series of adult patients (aged 18-64 years) who had primary care visits between January 1, 2010, and June 30, 2015, or established hypothyroidism between January 1, 2012, and June 30, 2015, across 3 health care delivery jurisdictions: Ontario, Canada; the US Veterans Health Administration; and the US employer-sponsored insurance market. Data analysis was performed from March 21, 2018, to October 31, 2019. Exposures: A December 2010 payment policy change that eliminated reimbursement of vitamin D screening in Ontario, Canada, and the subsequent release of Choosing Wisely recommendations against low-value use of vitamin D tests in February 2013 and triiodothyronine tests in October 2013 in the United States and both tests in October 2014 in Canada. Main Outcomes and Measures: Relative marginal effects (RMEs) comparing low-value testing rates after the release of Choosing Wisely recommendations with rates expected based on prerelease trends and the associated change in low-value vitamin D testing after the 2010 payment policy change in Ontario, Canada. Results: Of 54 223 448 total persons, 28 504 576 (52.6%) were female, with 17 895 458 persons (33.0%) aged 18 to 34 years, 11 101 985 (20.5%) aged 35 to 44 years, and 25 226 005 (46.5%) aged 45 to 64 years. The December 2010 policy eliminating reimbursement for low-value vitamin D screening in Ontario, Canada, was associated with a 92.7% (95% CI, 92.4%-93.0%) relative reduction in such screening. Corresponding Choosing Wisely recommendations were associated with smaller reductions: 4.5% (95% CI, 2.6%-6.3%) in Ontario, 13.8% (95% CI, 11.8%-15.9%) for US Veterans Health Administration, and 14.0% (95% CI, 12.8%-15.2%) for US employer-sponsored insurance. In contrast, low-value use of triiodothyronine testing did not change significantly in Ontario, Canada (RME, 0.3%; 95% CI, -1.4% to 2.0%) or the US Veterans Health Administration (RME, 0.7%; 95% CI, -4.7% to 6.4%) and increased (RME, 3.0%; 95% CI, 1.6%-4.4%) for US employer-sponsored insurance. Conclusions and Relevance: In this study, marginal reductions in the use of 2 low-value laboratory tests were associated with the release of related Choosing Wisely recommendations but a greater reduction in low-value vitamin D screening was associated with a previous payment policy change implemented in Ontario, Canada. These findings suggest that recommendations alone may be insufficient to significantly reduce use of low-value services and that pairing recommendations with policy changes may be more effective.