A patient ledger within a practice management system may be called a(n):

A patient ledger is essentially a record of all financial transactions related to a specific patient within a healthcare practice. It includes information such as charges for services provided, payments made by the patient, adjustments, and any balances owed. Referring to it as account history aligns with the terminology used in practice management systems, as it accurately describes a comprehensive history of the patient's account activity.

In contrast, the other terms do not fit this definition. An encoder typically relates to a tool used for assigning codes to diagnoses and procedures based on standardized coding systems, facilitating billing and insurance claims. A coder program is software designed to aid in the medical coding process, ensuring accuracy and compliance with coding guidelines. Lastly, an accounts payable report is used in managing a practice's outgoing payments and is not specific to the patient's financial record. Thus, the designation of "account history" is the most accurate term for what a patient ledger represents in a practice management system.