Evaluating an LLM-Assisted Workflow for Clinical Documentation: A Pilot Randomized Controlled Trial on Time and Quality

IMPORTANCELarge language models (LLMs) have been investigated for clinical documentation, with concerns about hallucinations and factual errors. Clinician review and revision of LLM-generated drafts are therefore considered essential, yet the impact of such workflow on both documentation time and quality remains unknown. OBJECTIVETo assess whether physician review and editing of LLM-generated drafts improves the time and quality of clinical documentation compared with clinician-only drafting in a randomized controlled trial setting. DESIGNSingle-center, parallel-group, prospective, randomized, open-label, blinded-endpoint (PROBE) pilot trial conducted from February 18 to March 14, 2025. SETTINGKyoto University Hospital, Department of Ophthalmology. PARTICIPANTSTwenty-one ophthalmology physicians were randomized; 17 completed the study, and 4 withdrew before initiating intervention. INTERVENTIONSParticipants were randomized to either the Clinician-in-the-loop group or the Clinician-only group. All participants created discharge summaries and referrals for six simulated patient records. In the Clinician-in-the-loop group, drafts were generated with an LLM assistant and then reviewed and edited by participants, whereas in the Clinician-only group, documents were drafted from scratch using matched templates. Unedited LLM drafts were additionally analyzed as the LLM-only group. MAIN OUTCOMES AND MEASURESDocument creation time (primary) and expert-rated document quality across six domains plus overall quality (secondary). RESULTSSeventeen physicians submitted 48 discharge summaries and 48 discharge referrals in the Clinician-in-the-loop group, 54 of each document type in the Clinician-only group, and 48 of each in the LLM-only group. For summaries, Clinician-in-the-loop was associated with shorter creation time versus Clinician-only ({beta} = -59.4 seconds; 95% CI, -118.1 to -0.8; P = .047). For referrals, clinician-in-the-loop required more time ({beta} = 94.8 seconds; 95% CI, 40.4 to 149.3; P<.001). In most quality domains for both document types, the clinician-in-the-loop workflow outperformed clinician-only drafting. LLM-only drafts were fastest but had the lowest quality. CONCLUSIONS AND RELEVANCEA clinician-in-the-loop approach improved document quality and accelerated documentation. Active clinician review of LLM-generated drafts is essential for clinical documentation, and such workflows may help enhance working conditions and patient care. TRIAL REGISTRATIONClinicalTrials.gov Identifier NCT07187050 Key PointsO_ST_ABSQuestionC_ST_ABSDoes a workflow in which clinicians review and edit LLM-generated drafts ("clinician-in-the-loop") improve the efficiency and quality of clinical documentation compared with clinician-only drafting? FindingsIn this single-center randomized controlled trial including 17 ophthalmology physicians, discharge summaries were significantly faster with the clinician-in-the-loop. Across both document types, clinician-in-the-loop drafts achieved higher quality scores than clinician-only documents. MeaningA clinician-in-the-loop workflow using LLMs can simultaneously enhance the efficiency and quality of clinical documentation; accordingly, active clinician review remains essential for improving working conditions and patient care overall.