Modifier -33: “Preventive Services”:
When the primary purpose of the service is the delivery of an evidence-based service in accordance with a US Preventive Services Task Force A or B rating in effect and other preventive services identified in preventive services mandates (legislative or regulatory), the service may be identified by appending modifier 33, Preventive Service, to the service. For separately reported services specifically identified as preventive, the modifier should not be used.
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