Benchmarking large language models against clinicians across hospital levels in cardiovascular decision-making: a cross-sectional vignette-based study

Large language models (LLMs) have showed strong performance on standardized medical examinations, yet their comparative clinical relevance against human clinicians remains limited. This study benchmarked the performance of DeepSeek-R1 and ChatGPT 4.0 against cardiovascular clinicians from different hospital levels in China. We conducted a cross-sectional, vignette-based assessment consisting of 100 standardized cardiovascular multiple-choice questions covering four competency domains: clinical reasoning (CR), frontier updates (FU), basic memory (BM), and emergency decision (ED). Thirty clinicians from six hospitals (three primary and three tertiary) were compared with two LLMs. Each question was executed five times per model, and run-to-run consistency was evaluated. Mean differences (LLM - clinician) with 95% confidence intervals (CIs) were estimated using nonparametric bootstrap resampling (10,000 iterations). Clinicians achieved a mean total score of 69.7 ± 7.9, whereas DeepSeek-R1 and ChatGPT-4.0 scored 97 and 95, respectively. The mean total score differences were + 27.3 points (95% CI 24.4-30.1) for DeepSeek-R1 and + 25.3 points (22.4-28.1) for ChatGPT 4.0. Both models outperformed clinicians in CR, FU, BM, and ED. Run-to-run agreement was high (DeepSeek-R1 κ = 0.73; ChatGPT 4.0 κ = 0.76). LLMs substantially outperformed clinicians in knowledge- and decision-based tasks while approaching clinician-level performance in CR. These findings suggest that LLMs may complement clinical expertise and enhance diagnostic consistency across hospital levels.