Which task must be performed by the RN and cannot be delegated?

The initial nursing assessment cannot be delegated — it requires the comprehensive judgment and analysis only an RN can provide. The initial assessment establishes the baseline, identifies acute and chronic issues, develops the nursing diagnoses, and is the foundation of the care plan. This is a nursing process activity (Assessment, Diagnosis, Planning, Implementation, Evaluation — ADPIE) and the Assessment step is RN-exclusive. Subsequent data collection (such as routine vital signs on stable clients, intake/output measurements, focused observations) can be delegated to LPNs or UAPs with appropriate parameters and reporting expectations, but the comprehensive assessment, analysis of findings, and care planning are RN responsibilities. Bathing, vaccine administration (depending on state and setting), and bathroom assistance are delegable tasks within appropriate scope.