The major difference lies in the participation requirements. The Merit-based Incentive Payment System (MIPS) is the default track under the Quality Payment Program (QPP) for eligible clinicians. Those who are eligible must participate to avoid a negative payment adjustment (penalty), making it effectively mandatory. In contrast, Alternative Payment Models (APMs) are voluntary programs that offer different payment approaches. Clinicians can choose to join an APM if they meet its specific criteria, but they are not required to do so.

B. This option incorrectly reverses the participation requirements; APM participation is voluntary, while MIPS is the default track with penalties for non-participation.

C. This is incorrect because MIPS participation is not truly voluntary for eligible clinicians who wish to avoid a financial penalty.

D. This is incorrect because participation in APMs is a voluntary choice for providers and practices, not a requirement.

1. Centers for Medicare & Medicaid Services (CMS). (n.d.). Quality Payment Program Overview. "The Quality Payment Program has two tracks you can choose from: Advanced APMs or MIPS." This language indicates a choice, making APMs voluntary. Retrieved from qpp.cms.gov.

2. Centers for Medicare & Medicaid Services (CMS). (2023). MIPS Participation and Eligibility. This official resource details the criteria for required MIPS participation and the associated payment adjustments for non-participation. Retrieved from qpp.cms.gov/mips/mips-eligibility.

3. McClellan, M., & Thoumi, A. (2017). The Quality Payment Program: A new day for value-based care. JAMA, 317(11), 1119-1120. https://doi.org/10.1001/jama.2017.1670. (Describes MIPS as the default pathway and APMs as an alternative).