Final answer:
Insurance information is the data element included in the UACDS but not in the UHDDS.
Step-by-step explanation:
The data element that is included in the UACDS but not in the UHDDS is Insurance information. UACDS stands for Uniform Ambulatory Care Data Set, which is used for outpatient settings, while UHDDS stands for Uniform Hospital Discharge Data Set, which is used for inpatient hospital settings. Insurance information is typically not collected in the UHDDS, but it may be included in the UACDS to track patients' insurance coverage for billing and reimbursement purposes.