Supplement 2. Cost data caterogization and buckets creation

This supplement describes a methodology for the categorization of cost data into defined "buckets" based on CPT4 and UB codes.<br>The process follows a hierarchical logic, as illustrated in an accompanying flowchart:<br><b>Primary Categorization</b>: The system first attempts to assign a category using CPT4 code groupings, which are given primary emphasis.<b>Fallback Categorization</b>: If a CPT bucket is not available for a given record, the system uses the corresponding UB (Uniform Billing) bucket as a fallback.<b>Default Categorization</b>: Records that cannot be mapped to a bucket using either the CPT4 or UB codes are labeled as "CDW".