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EMSDialog: Synthetic Multi-person Emergency Medical Service Dialogue Generation from Electronic Patient Care Reports via Multi-LLM Agents
Xueren Ge, Sahil Murtaza, Anthony Cortez, Homa Alemzadeh
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Summary
EMSDialog is a synthetic multi-party medical dialogue generation pipeline that uses an EHR-grounded, multi-agent approach to create realistic EMS conversations. By integrating rule-based checkers for concept and topic flow with LLM-based refinement, the pipeline generates 4,414 dialogues annotated with diagnoses, speaker roles, and topics. The study demonstrates that training models on EMSDialog improves the accuracy, timeliness, and stability of conversational diagnosis prediction.
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Multi-Agent Pipeline â generates â EMSDialog
confidence 100% · We introduce an ePCR-grounded, topic-flow-based multi-agent generation pipeline... The pipeline yields EMSDialog
EMSDialog â groundedin â ePCR
confidence 100% · The pipeline yields EMSDialog, a dataset of 4,414 synthetic multi-speaker EMS conversations based on a real-world ePCR dataset
EMSDialog â improves â Conversational Diagnosis Prediction
confidence 95% · Results show that EMSDialog-augmented training improves accuracy, timeliness, and stability of EMS conversational diagnosis prediction.
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Abstract
Abstract:Conversational diagnosis prediction requires models to track evolving evidence in streaming clinical conversations and decide when to commit to a diagnosis. Existing medical dialogue corpora are largely dyadic or lack the multi-party workflow and annotations needed for this setting. We introduce an ePCR-grounded, topic-flow-based multi-agent generation pipeline that iteratively plans, generates, and self-refines dialogues with rule-based factual and topic flow checks. The pipeline yields EMSDialog, a dataset of 4,414 synthetic multi-speaker EMS conversations based on a real-world ePCR dataset, annotated with 43 diagnoses, speaker roles, and turn-level topics. Human and LLM evaluations confirm high quality and realism of EMSDialog using both utterance- and conversation-level metrics. Results show that EMSDialog-augmented training improves accuracy, timeliness, and stability of EMS conversational diagnosis prediction.
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- Source: https://arxiv.org/abs/2604.07549v1
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EMSDialog: Synthetic Multi-person Emergency Medical Service Dialogue Generation from Electronic Patient Care Reports via Multi-LLM Agents Xueren Ge 1 , Sahil Murtaza 1 , Anthony Cortez 2 , Homa Alemzadeh 1 1 School of Engineering and Applied Sciences, University of Virginia, Charlottesville, VA, USA 2 School of Medicine, University of Virginia, Charlottesville, VA, USA zar8jw, vpn9ej, aec3gp, ha4d@virginia.edu Abstract Conversational diagnosis prediction requires models to track evolving evidence in stream- ing clinical conversations and decide when to commit to a diagnosis.Existing medi- cal dialogue corpora are largely dyadic or lack the multi-party workflow and annotations needed for this setting. We introduce an ePCR- grounded, topic-flow-based multi-agent gen- eration pipeline that iteratively plans, gener- ates, and self-refines dialogues with rule-based factual and topic flow checks. The pipeline yields EMSDialog, a dataset of 4,414 synthetic multi-speaker EMS conversations based on a real-world ePCR dataset, annotated with 43 diagnoses, speaker roles, and turn-level top- ics. Human and LLM evaluations confirm high quality and realism of EMSDialog using both utterance- and conversation-level metrics. Re- sults show that EMSDialog-augmented training improves accuracy, timeliness, and stability of EMS conversational diagnosis prediction. 1 Introduction Conversational diagnosis prediction aims to infer a patientâs likely condition during clinical conversa- tions, issuing early yet reliable diagnosis that can guide timeâcritical actions (e.g., airway manage- ment, glucose checks, stroke alerts). This is a vital capability for conversational diagnostic agents that either replace doctors by conducting diagnostic interviews with patients (Fan et al., 2025; Chen et al., 2025; Tu et al., 2025) or assist doctors by suggesting real-time diagnoses and next-step treat- ments (Shu et al., 2019; Weerasinghe et al., 2024). Unlike Electronic Health Record (EHR)-based diagnosis prediction (Rios and Kavuluru, 2018; Ge et al., 2024) where full EHR data is often used as input, conversational diagnosis prediction models must reason over incomplete streaming informa- tion, update predictions turn by turn, and decide when to commit versus defer on a final prediction. Figure 1: Qwen3-series model performance on conver- sational diagnosis prediction for cardiac arrest scenario Training and evaluating models for this task de- mands realistic medical conversation data that re- flects how care actually happens along with diag- nosis annotations. Medical conversations are inher- ently multi-party, with information being elicited, relayed, and verified across several speakers with distinct roles, topics, and access to context. Emer- gency Medical Services (EMS) (Weerasinghe et al., 2025) exemplifies this setting, where medics coor- dinate with partners and dispatch while interacting with the patient and bystanders, each contributing role-specific evidence (e.g., scene safety, chief com- plaint, medications, last-known-well). However, existing medical corpora fall short for this setting: (i) Online doctorâpatient dialogue datasets (mostly from Chinese online-forums) (Wei et al., 2018; Xu et al., 2019; Zhang et al., 2020; Zhou et al., 2021; Liu et al., 2022; Li et al., 2021; Shi et al., 2023; Zeng et al., 2020) are typically asynchronous, dyadic, diverging from realistic real- time operational workflows and offering limited di- agnosis labels; (i) EHRâgrounded human role-play datasets (Abacha et al., 2023; Papadopoulos Korfi- atis et al., 2022; Saley et al., 2024) improve case re- alism but still assume two speakers and seldom pro- vide diagnosis annotations; and (i) Synthetic dia- logue datasets generated by rules (Fansi Tchango et al., 2022; Seo and Lee, 2024) or LLMs (Wang et al., 2024) although easily scalable, often ne- glect realistic dialogue topic flow, multi-party set- arXiv:2604.07549v1 [cs.CL] 8 Apr 2026 Data characteristicsGeneration methodData Use DatasetSettingLang. #Roles #Dx Topic #U/D Gen.Src.CheckerRefinerTasks Real Dxy (Xu et al., 2019)Telehealthcn25ââHumanWebâDiagnosis Pred MedDialog (Zeng et al., 2020)Telehealth cn,en296â3.3 HumanWebâGeneration MedDG (Liu et al., 2022)Telehealthcn212â21.6 HumanWebâNER MidMed (Shi et al., 2023)Telehealthcn24â11.8 HumanWebâGeneration MTS-Dialogue (Abacha et al., 2023) Clinicalen2ââ9.0 Human RoleplayâNote2Diag MediTOD (Saley et al., 2024)Clinicalen2ââ95.6 HumanâGeneration EMSAudio (Weerasinghe et al., 2024) EMSen3.77â54.5 Human RoleplayâAudio2Text EgoEMS (Weerasinghe et al., 2025)EMSen4.13â128.5 Human RoleplayâActivity Recognition Synthetic DDXPlus (Fansi Tchango et al., 2022) Clinicalen249â33.1RuleâDiagnosis Pred NoteChat (Wang et al., 2024)Clinicalen2ââ62.5 LLMEHRStyleâNote2Diag DiagESC (Seo and Lee, 2024)Mentalen25ââLLMPHQ-9ââGeneration HQMedical (Ge et al., 2025)Clinicalcn2ââ54.0 LLMEHRStyleâNote2Diag MedSynth (Mianroodi et al., 2025)Clinicalen22001â55.0 LLMEHRStyleâNote2Diag EMSDialog (ours)EMSen5.243â114.3 LLMEHRTopic, Fact, StyleâDiagnosis Pred Table 1: Comparison of real vs. synthetic medical multi-turn dialogue datasets. #Roles = Average number of speaker roles per dialogue. #Dx = Number of diagnosis classes. #U/D = Average number of utterances per dialogue. tings, and rich annotations required for downstream tasks such as conversational diagnosis prediction. These gaps motivate creating multi-speaker, oper- ationally realistic datasets with task-aligned diag- nosis annotations, to train and evaluate models on not only what to predict, but also when to commit. On the other hand, off-the-shelf zero-shot LLMs (Li et al., 2024; Tu et al., 2025; Ge et al., 2026), although a plausible choice as conversa- tional diagnostic agents, often fail to produce re- liable, stable predictions in dynamic, turn-by-turn conversational settings (Laban et al., 2025). In particular, as shown in Figure 1, they (i) make incorrect, early, highly confident guesses when evi- dence is still sparse, and (i) exhibit high prediction volatility, frequently switching their outputs as new information arrives instead of converging to a con- sistent diagnosis. To address these gaps, we propose a multi-agent synthetic dialogue generation pipeline for creat- ing realistic, multi-speaker medical conversations grounded in real-world clinical records. We lever- age the pipeline to generate a synthetic EMS dia- logue dataset and use it to train and evaluate models for conversational diagnosis prediction. Our contri- butions are threefold: âąWe propose a scalable, EHR-grounded, multi- agent pipeline for synthetic multi-party dialogue generation that ensures clinical factuality, proce- dural realism, and stylistic naturalness through an iterative critique-and-refine loop driven by a hybrid suite of deterministic rule-based checkers for concept and topic flow, alongside an LLM- based style checker. âą We introduce EMSDialog, an EMS-specific syn- thetic dataset of 4,414 realistic multi-party con- versations, generated based on a real-world ePCR dataset and annotated with 43 diagnoses, turn- level speaker roles and topics. Human expert and LLM-based evaluations show strong qual- ity at both utterance level (realism, safety, role accuracy, groundedness) and conversation level (logical flow, factuality, diversity). Datasets and code will be publicly released upon publication. âąWe demonstrate the downstream utility of EMS- Dialog by training models of different sizes for conversational diagnosis prediction and evalu- ating them on real-world EMS conversations. Experiments show that EMSDialog-augmented training improves prediction accuracy, timeliness, and stability, and combining synthetic with real data yields the strongest overall performance. 2 Related Works 2.1 Real-world Medical Dialogue Datasets As shown in Table 1, many publicly-available real telehealth dialogue corpora are web-crawled from Chinese online forums (Wei et al., 2018; Xu et al., 2019; Zhang et al., 2020; Zhou et al., 2021; Liu et al., 2022; Li et al., 2021; Shi et al., 2023; Zeng et al., 2020). However, they often diverge from real clinical topic flows (e.g., chief complaint, primary assessment) and provide limited supervi- sion (e.g., symptom tags and small diagnosis sets). Datasets constructed via human role-play grounded in EHR (Abacha et al., 2023; Papadopoulos Korfi- atis et al., 2022; Saley et al., 2024) improve realism but typically lack detailed diagnosis labels, lim- iting use for downstream tasks such as diagnosis prediction. Although EgoEMS (Weerasinghe et al., 2025) collects small set of realistic human roleplay EMS dialogues, the data size and label set is far too small to train a reliable model for real-world use. Moreover, most prior works assume dyadic doctorâpatient chats, whereas real care-especially in EMS-involves multi-party coordination. These gaps motivate datasets with (i) multi-speaker, realis- tic dialogues that faithfully mirror operational care environments, and (i) task-aligned annotations. 2.2 Synthetic Medical Dialogue Generation Early efforts on data synthesis adopted rule- based pipelines with handcrafted templates or con- straints (Fansi Tchango et al., 2022; Seo and Lee, 2024). Recent work leverages LLMs (Li et al., 2023), exploiting their fluency while adding guardrails. In EHR-grounded dialogue generation, (ALMutairi et al., 2024; Das et al., 2024; Ge et al., 2025) inject predefined rules in prompts (e.g., symptom coverage, turn struc- ture) to steer LLMs toward higher-quality con- versations. NoteChat (Wang et al., 2024) further pipelines the process by extracting symptoms from EHRs and role-playing doctorâpatient interactions to yield clinically plausible dialogues. But, both approaches overlook dialogue logical structures (e.g., topic flows (Du et al., 2025)), multi-party con- versations, and annotations for downstream tasks. Unlike existing methods that rely on unverified LLM-based refinement, we propose a framework that guarantees procedural realism and factuality in synthetic dialogues by integrating deterministic, rule-based verification into a strict repeat-until-pass refinement loop. 2.3 Conversational Diagnosis Prediction Previous work on conversation forecasting (Chang and Danescu-Niculescu-Mizil, 2019; Kementched- jhieva and SĂžgaard, 2021; Yuan and Singh, 2023; Zhang et al., 2025) focused on detecting impending conversational events within a transcript. However, forecasting is typically framed as binary classifi- cation with an early stop once a âderailmentâ is predicted. These works did not focus on continu- ous diagnosis prediction based on each utterance in the conversation. On the other hand, prior work on diagnosis prediction either assumes static EHR snapshots (Ma et al., 2018, 2017; Ge et al., 2024; Niset et al., 2025) or the whole conversation as in- put for multi-label classification (Wei et al., 2018; Xu et al., 2019). Recent work on conversational diagnostic agents uses LLMs as a replacement for doctors to conduct direct diagnostic dialogues with patients (Sun et al., 2024; Tu et al., 2025). Here we focus on conversational diagnosis prediction which is the task of multi-label diagnosis classification at each utterance in a dialogue between caregivers and patient for assisting with timely diagnosis in emergency scenarios (Weerasinghe et al., 2024). 3 Preliminaries 3.1 Electronic Patient Care Report (ePCR) ePCRs are the primary documentation used in EMS to record real-time patient care during emergency incidents (Rahman et al., 2020; Kim et al., 2021; Ge et al., 2024). As shown in Figure 2a, an ePCR combines structured fields, including Chief Com- plaint, History of Present Illness (e.g., medical his- tory, current medications, allergies), vital signs, and interventions (procedures, medications), with a free-text medic narrative describing the encounter and protocols (diagnoses) used for treating patients. 3.2 EMS Topic Flow We define the EMS topic flow based on official guidelines (National Registry of Emergency Medi- cal Technicians, 2016; Old Dominion Emergency Medical Services Alliance, 2022). As shown in Fig. 2b, EMS encounters begin with Introduction âChief ComplaintâResponse Test (GCS) to choose the branch. If the patient is conscious, the dialogue proceeds to Primary Assessment (Check- ing A.B.C.:Airway,Breathing,Circulation.) and Secondary Assessment, followed by HPI (Check- ing S.A.M.P.L.E.:Signs/Symptoms,Allergies, Medications,Past medical history,Last oral in- take,Events leading up to illness/injury) and Pain Assessment (Checking O.P.Q.R.S.T.:Onset, Provocation/Palliation, Quality, Region/Radiation, Severity,Time.). If the patient is comatose, history- taking is deferred; providers prioritize Primary then Secondary Assessment. Across both branches, Vitals and Interventions may interleave with assess- ments. When the case exits to protocol, medics determine a working diagnosis and transition from general care to protocol-specific steps. During transport, Interventions and Reassessment continue. The topic flow yields a realistic, modular structure for EMS dialogues and supports fine-grained su- pervision and timing decisions. Detailed topic flow definitions are in Appendix A.1. 4 Methodology 4.1 Synthetic Dialogue Generation Pipeline As shown in Figure 2c, our synthetic data gener- ation pipeline consists of five modules, including Figure 2: a) ePCR; b) EMS Topic Flow; c) Synthetic Dialogue Generation Pipeline; d) Synthetic Dialogue Example. Color-highlighted text across (a) and (d) demonstrates the factual grounding of generated dialogue concepts to the original ePCR data. three LLM agents for topic flow planning, dialogue generation, and refinement, as described next. 4.1.1 Extractor The first module in the pipeline extracts impor- tant medical concepts from input ePCR to pre- serve them through subsequent LLM stages and ensure they are explicitly incorporated in the gen- erated dialogue. For structured data, we parse the concepts using regular expressions. For un- structured notes, we extract key EMS concepts us- ing the state-of-the-art (SOTA) rule-based clinical NER toolkit, MedSpaCy (Eyre et al., 2021) with QuickUMLS (Soldaini and Goharian, 2016) (See more details in Appendix A.3). We also use regu- lar expressions to extract important features (such as GCS score) which govern the topic flow. For example, if GCS†8(coma), EMS response is initiated with Primary Assessment, but if GCS> 8 (conscious), it begins with HPI/Pain Assessment. 4.1.2 Checkers We incorporate three independent checkers to provide actionable feedback on concept errors, topic-flow violations, and style issues to the LLM agents and prompt them to self-refine the gener- ated plan/dialogue (Madaan et al., 2023). The PLANNER and GENERATOR agents iteratively re- vise their outputs and cannot proceed until all hard constraints by rule-based Concept and Topic Flow checkers are satisfied (e.g., no missing or halluci- nated concepts; no invalid topic transitions or hal- lucinated topics). The LLM-based Style checker proposes style critiques to the REFINER agent. Concept Checker extracts concepts from the source ePCR and from the generated Plan/Dialogue using the same MedSpaCy concept extractor. The two concept sets are then aligned in a two-stage procedure: (i) syntactic matching, where two con- cepts are matched only if their surface forms are an exact string match; and (i) semantic matching, where any remaining unmatched concepts are em- bedded with GatorTron (Yang et al., 2022) and paired based on cosine similarity, considering two concepts equivalent if their similarity is at least 0.8. After matching, concepts present in the ePCR but not matched in the Plan/Dialogue are labeled as missing (FN), while concepts appearing only in the Plan/Dialogue are labeled as hallucinated (FP). Topic Flow Checkervalidates that the dialogueâs topic sequence complies with allowable topic flow rules. We define a directed graphG = (V,E) over topics, represented as an adjacency listA = current : [allowed next topics]. For each topic pair(t i ,t i+1 )in consecutive utterances, we check whethert i+1 âA[t i ]. The checker flags two error types: (1) transition error when there is no edge fromt i tot i+1 ; and (2) hallucinated topic when t i /â V (i.e., the topic is not in the ontology). Style Checker verifies if the dialogue style sat- isfies a set of domain-specific requirements (See prompt in Appendix Figure 13), including realis- tic EMS dialogues (Weerasinghe et al., 2025) as exemplars and a rubric describing typical EMS di- alogue patterns, authored by an EMS expert (See Appendix Figure 17). This checker acts as an LLM judge: if violations are detected, it returns struc- tured critiques with concrete revisions based on the rubric; otherwise, it issues a pass. 4.1.3 Planner The PLANNER LLM proposes a dialogue plan given the input ePCR, the topic flow, and ex- tracted EMS concepts (see prompt in Appendix Figure 14). The plan is encoded as a sequence of tuples(topic, evidence), where evidence cites spe- cific ePCR fields. The CHECKER validates the plan for (i) concept coverage and (i) topic flow, and any violations are returned as structured feedback for iterative revision by the PLANNER. The plan is ac- cepted once no concept or topic-flow errors remain. This is to enforce dialogue logical structure and ensure every turn is supported by ePCR evidence. 4.1.4 Generator The GENERATOR LLM produces an initial dia- logue draft, including utterances and their assigned roles (e.g., medic, partner, patient, bystanders) at each turn, which is explicitly grounded in the ePCR evidence cited in the plan (see prompt in Appendix Figure 15). The CHECKER evaluates the (i) con- cept coverage and (i) topic flow of each utterance, returning targeted feedback to the GENERATOR and iterating until all constraints are satisfied. The goal is to produce a first-pass dialogue that strictly adheres to the validated plan and ePCR evidence. 4.1.5 Refiner Although the generation stage yields a dialogue that adheres to the topic flow and ePCR evidence, it can read as unnatural. For example, this often occurs when the dialogue âtellsâ instead of âshowsâ behaviors: a patient is simply labeled âcombativeâ rather than shouting or resisting; or a medic de- clares a patient as âoriented to placeâ instead of asking orientation questions like, âWhere are we?â. The REFINER LLM edits the dialogue for coherent turn-taking, natural phrasing, and clinically plausi- ble actions based on expert rubrics and exemplars, while preserving evidence grounding (see prompt in Appendix Figure 16). The CHECKER checks the (i) concept coverage, (i) topic flows and the (i) styles issue, returning the feedback to REFINER to further revise the dialogue. The goal is to polish the dialogue for realism while preserving factuality. This refinement loop runs for at most 5 iterations or terminates early once the dialogue satisfies all checks. We set the maximum iteration as 5 because the mean number of iterations needed to fix con- cept and topic flow errors in previous âPlanâ and âGenerateâ stages is 4.3. 5 Experiments We conduct both intrinsic and extrinsic evaluations of our synthetic dialogue generation pipeline to answer the following research questions: RQ1: What is the quality of synthetic multi-person dialogue data generated by the pipeline? RQ2: How can synthetic dialogue data help with conversational diagnosis prediction? 5.1 Dataset and Baselines ePCR: We leverage a real-world EMS ePCR dataset containing 4,417 pre-hospital reports an- notated with 43 EMS protocol labels to ground our synthetic EMS dialogue generation. These records were collected from a regional ambulance agency in the U.S. between 2017 and 2020. All private information has been de-identified. More ePCR details is provided in Appendix A.4 Real-world EMS Dialogue: We split 149 de- identified real-world EMS dialogues (Weerasinghe et al., 2024, 2025) into train (89) and test (60), where the 89 dialogues form our Real training set. Synthetic EMS Dialogue: We benchmark our ap- proach against five methods. To ensure fairness, all models are conditioned on the same source ePCRs. The baselines are categorized into single-agent (iâ iv) and multi-agent (vâvi) frameworks: âą Single-Agent Baselines: â 0-Shot: Direct prompting using the ePCR. â 0-Shot + Rules: Direct prompting augmented with professional EMS rules. â CoT (Wei et al., 2022): Chain-of-thought prompting using the ePCR and one real-world EMS exemplar. â CoT + Rules: CoT prompting augmented with both the exemplar and EMS rules. âą Multi-Agent Frameworks: âNoteChat (Wang et al., 2024): The state-of- the-art medical dialogue generator, adapted by replacing its default clinical prompts with our EMS exemplars. â EMSDialog (Ours): Our proposed pipeline in- tegrating the ePCR, an exemplar, medical rules, and the EMS Topic Flow constraint. Dataset statistics are provided in Appendix A.4. All inference is executed locally using Qwen3- 32B (Yang et al., 2025) deployed on NVIDIA A100 GPUs via VLLM (Kwon et al., 2023). The com- plete prompts can be found in Figure 18â21. 5.2 Intrinsic Evaluation We conduct intrinsic evaluation of the quality of generated dialogues at two levels of granularity, conversation-level and utterance-level. We evalu- ate 43 sample dialogues (one per diagnosis class) via manual review by a certified EMS professional, and the full set of 4,411 ePCR-derived dialogues using the âLLM-as-a-judgeâ (Zheng et al., 2023) method. For each input ePCR, the dialogue gener- ated by our pipeline is compared to those generated by the baselines. To mitigate ordering bias, we randomized the presentation order of the four dia- logues for both human experts and LLM judges in our experiments. Additionally, we employ two independent open-source models, Qwen3-235B (Yang et al., 2025) and Llama-3.3-70B (Dubey et al., 2024), as LLM judges to preserve privacy while maintaining evaluation quality. Conversation-level Metrics.At the conversation level, each dialogue is evaluated via these metrics: âąLogical Structure (â): Measured on a 5-point Likert scale (1â5), assessing if the dialogue fol- lows a coherent EMS topic progression. âąOverall Ranking (â): A comparative ranking of the four generated dialogues, summarized using Mean Reciprocal Rank (MRR). âą Factuality (â): Measured as concept-level pre- cision and recall (P/R) between the source ePCR and the generated dialogue, using (i) NER- extracted concepts (Fac NER ) for the full dataset and (i) human-annotated concepts for the subset of 43 manually-evaluated cases (Fac H* ). âąDiversity (â): Calculated using Self-BLEU (Montahaei et al., 2019) over all dialogues gener- ated by each method, with lower values indicat- ing higher diversity (less self-repetition). Utterance-level Metrics.We cast utterance-level evaluation as a binary classification task. Human and LLM judges assign a âYesâ or âNoâ label for each metric. Results are reported as an aggregate âYesâ rate (%) across all evaluated utterances: âąRealism (â): Whether the utterance sounds natu- ral and is likely generated by a human. âą Safety (â):For responder utterances only; whether the utterance contains actions or de- cisions that violate established EMS protocol guidelines (diagnosis knowledge) (Old Domin- ion Emergency Medical Services Alliance, 2022) or could potentially harm the patient. âą Role Accuracy (â): Whether the speaker role matches the EMS dialogue context. âąGroundedness (â): Whether EMS concepts in the utterance are supported (syntactically, seman- tically or inferably) by the associated ePCR. 5.3 Extrinsic Evaluation We evaluate whether synthetic dialogue data can help fine-tune SOTA LLMs for improved conversa- tional diagnosis prediction. Formally, at dialogue turnt, the model is given the accumulated tran- script prefixX t = (u 1 ,u 2 ,...,u t ), up to utter- anceu t and produces a probabilityp t (l)(confi- dence) for each diagnosis labell â L. At each turnt, the model must (i) update its belief over diagnoses and (i) decide whether to commit to a final prediction or defer to gather more evidence. To simplify the problem, we convert modelâs prob- abilities to predictions using a fixed thresholdÏ: Ë Y t = l â L : p t (l) â„ Ï. If no label exceedsÏ, the model defers at turn t. We fixed Ï = 0.5. We fine-tune Qwen3-0.6B/4B with LoRA (Hu et al., 2022) under three regimes: Real-only (89 real dialogues), Synthetic-only (each synthetic source), and Real+Synthetic (Real combined with EMSDi- alog). For all fine-tuning runs, we use an 80:20 trainâvalidation split on the train and select the best checkpoint by validation performance. Training Strategies. We follow two established strategies for conversation forecasting: (i) Static training (Chang and Danescu-Niculescu-Mizil, 2019), which trains on the full dialogue prefix, learning to predict a label from the set of diag- noses based on the aggregated context; (i) Dy- namic training (Kementchedjhieva and SĂžgaard, 2021), which expands each dialogue into multiple training instances by unrolling the lastKprefixes (e.g.,u 1:T ,· ,u 1:TâK ), so the model is explicitly trained to make predictions from earlier, partial ev- idence. More training details are in Appendix A.5 Testing. At inference time, we evaluate all mod- els in a dynamic (turn-by-turn) setting. Given the growing transcript prefix, the model emits diag- noses at each turn when its confidence exceedsÏ. We report results on the held-out 60 real-world test dialogues, averaged over random seeds (0/1/42). Conversation-levelUtterance-level MethodLogic (â)MRR (â)Fac NER (â)Fac H* (â)Diversity (â)Realism (â)Safety (â)Role Acc (â)Groundedness (â) H* / LLM (1â5)H* / LLM (%)P / R (%)P / R (%)Self-BLEU (%)H* / LLM (%)H* / LLM (%)H* / LLM (%)H* / LLM (%) 0-shot1.85 / 2.4531.14 / 38.7571.32/ 55.8867.69/ 64.7140.3644.96 / 73.6896.77 / 95.7696.03 / 87.3980.76 / 75.85 0-shot+Rules â / 3.55 â / 50.5873.58/ 54.1369.23/ 66.8865.73 â / 63.91 â / 94.88 â / 95.34 â / 77.12 CoT3.05 / 3.5557.50/ 58.5575.76/ 58.7968.15/ 66.0940.4385.23/ 80.8299.85 / 95.4698.51 / 93.5587.08 / 85.79 CoT+Rules â / 3.80 â / 55.3378.23/ 54.7774.91/ 68.5661.59 â / 76.25 â / 98.21 â / 95.77 â / 86.33 NoteChat1.80 / 2.4331.25 / 39.1685.63/ 68.4080.12/ 74.2168.9739.86 / 85.18100.00/ 97.40100.00/ 98.3095.23/ 87.49 EMSDialog 4.25 / 4.55 87.50 / 81.92 93.70/ 73.72 91.06/ 82.8053.08 97.93 / 92.18 100.00 / 98.64 100.00 / 99.69 99.23 / 92.83 Table 2: Intrinsic Evaluation: Conversation- and Utterance-level performance of synthetic dialogues generation methods. H*: human evaluation on a 43-scenario subset. The best and runner-up results are in bold andunderlined. ModeSize Train DataPrompt First Acc (â) / ConfLast Acc (â) / Conf Earliness (â) (1st / 1st-correct) Edit Overheads (â) No Train 4B â0-shot 37.78 ±0.79 /88.57 ±0.44 60.22 ±0.79 /93.78 ±0.46 93.02 ±0.06 /80.20 ±1.63 83.51 ±0.34 âCoT 30.00 ±1.36 /88.37 ±1.11 61.67 ±2.72 /95.98 ±0.00 95.18 ±0.08 /81.73 ±0.44 73.26 ±0.29 32B â0-shot 63.89 ±0.79 /88.07 ±0.15 80.56 ±3.14 /94.20 ±0.20 92.41 ±0.00 /84.93 ±0.93 57.11 ±0.71 âCoT 51.11 ±2.08 /81.60 ±0.79 76.67 ±1.36 /93.07 ±0.37 94.44 ±0.08 /88.73 ±1.05 60.32 ±1.20 Static Train4B Realâ 58.23 ±4.57 /67.38 ±1.26 63.98 ±1.34 /78.53 ±1.26 90.10 ±2.17 /80.81 ±2.13 69.07 ±1.32 0-shotâ 68.33 ±2.08 /69.27 ±2.47 70.78 ±0.00 /85.18 ±3.33 81.32 ±1.75 /82.47 ±2.96 61.91 ±2.92 0-shot+Rulesâ 70.08 ±1.30 /70.27 ±2.28 70.92 ±2.48 /89.11 ±3.03 79.89 ±3.62 /79.08 ±4.31 65.07 ±3.59 CoTâ 67.22 ±2.08 /66.00 ±1.96 75.89 ±2.08 /84.95 ±1.33 82.21 ±1.11 /83.01 ±0.70 62.12 ±2.77 CoT+Rulesâ 69.80 ±1.84 /68.21 ±1.05 76.00 ±1.03 /82.74 ±3.54 83.57 ±2.24 /80.41 ±3.08 63.39 ±3.66 NoteChatâ 69.78 ±3.42 /61.08 ±2.23 75.44 ±2.83 /83.86 ±3.85 80.90 ±7.49 /79.97 ±7.04 54.09 ±1.52 EMSDialogâ 70.56 ±1.57 /75.49 ±2.99 77.78 ±1.57 /92.52 ±1.09 87.32 ±1.75 /86.55 ±0.96 47.57 ±1.95 EMSDialog+Real â 75.25 ±0.67 /86.62 ±0.48 82.05 ±1.69 /95.64 ±1.19 90.46 ±1.69 /88.70 ±1.98 35.84 ±0.98 Dynamic Train 4B Realâ 59.95 ±3.19 /70.53 ±2.39 67.21 ±1.78 /89.48 ±1.03 90.13 ±0.92 /81.14 ±1.38 58.32 ±0.64 0-shotâ 70.67 ±0.40 /76.46 ±2.78 72.22 ±2.08 /92.23 ±1.29 86.23 ±3.20 /85.66 ±0.57 46.49 ±0.14 0-shot+Rulesâ 69.41 ±3.30 /70.11 ±2.98 74.50 ±1.10 /90.20 ±1.74 78.12 ±4.22 /77.35 ±3.29 44.69 ±1.20 CoTâ 71.11 ±2.08 /83.31 ±2.36 73.33 ±1.36 /94.30 ±1.73 86.18 ±1.26 /86.08 ±1.29 42.95 ±1.99 CoT+Rulesâ 71.40 ±1.27 /72.76 ±2.94 75.93 ±1.76 /90.15 ±1.32 78.76 ±2.62 /77.81 ±3.77 42.51 ±1.53 NoteChatâ 72.44 ±1.57 /81.80 ±2.81 76.11 ±0.79 /94.06 ±0.71 83.97 ±0.14 /86.63 ±0.50 51.18 ±1.20 EMSDialogâ 74.67 ±0.79 /84.34 ±2.65 78.89 ±1.36 /94.11 ±2.56 87.03 ±0.59 /86.70 ±0.60 34.75 ±1.27 EMSDialog+Real â 76.84 ±2.68 /87.06 ±2.92 83.56 ±1.34 /96.36 ±0.19 88.96 ±0.13 /89.34 ±0.38 31.99 ±2.09 Table 3: Conversational diagnosis prediction results of Qwen3-4B/32B models. Evaluation Metrics. We use these metrics: âąFirst Acc (â) / Conf: Accuracy/confidence of the first label the model commits to (i.e., when it stops deferring). âąLast Acc (â) / Conf: Accuracy/confidence of the last committed label given the full dialogue. âąEarliness (â) (Gupta et al., 2020): How early a commitment occurs,1â t pred T , wheret pred is the turn of the first commit andTis the dialogue length. We report two earliness metrics: the 1st turn where any diagnosis exceeds the decision threshold and the 1st Correct turn where the com- mitted prediction matches the ground truth. âąEdit Overheads (â) (Hrycyk et al., 2021): Fraction of unnecessary prediction flips,1 â necessary changes total changes ,where a change is necessary only if the first commit is wrong and later flips even- tually reach the ground truth label. More details on metrics are in Appendix A.6. 6 Experimental Results 6.1 Intrinsic Evaluation (RQ1) EMSDialog achieves the best intrinsic perfor- mance based on multiple metrics compared with other baselines. At the conversation level, EMS- Dialog attains the highest Logical Structure (H â /LLM:4.25/4.55) and the best ranking (MRR) (H â /LLM:87.50/81.92), indicating more coherent dialogue flow and better preference ranking compared to baselines. More importantly, EMSDialog also yields the best factuality (P/R: 93.70/73.72) by NER model (Concept Checker) and (P/R:91.06/82.80) by human experts who checked both syntactic and semantic similar con- cepts. Meanwhile, diversity remains competitive and better than NoteChat. 0-shot baselines demon- strate the highest diversity (lowest Self-BLEU), but at the cost of poor factuality and other quality met- rics. At the utterance level, EMSDialog yields clear gains in Realism (â=8.2%) and Ground- edness (â=6.1%) compared to the SOTA base- line (NoteChat), indicating that its generated ut- terances align more closely with the source EMS evidence while better preserving the realistic re- sponses. For Safety(â=1.3%) and Role Accu- racy(â=1.4%), EMSDialog provides smaller but consistent improvements over the baselines. These results demonstrate that our approach produces dia- logues that are not only more coherent and realistic than SOTA baselines, but also more grounded in ePCR input. Appendix A.7 also presents the de- Gen+Plan+Refine+Check 60 65 70 75 80 (a) Last Acc( ) Gen+Plan+Refine+Check 40 60 80 (b) Edit OH( ) Gen+Plan+Refine+Check 0 25 50 75 100 (c) Conv-level Logic() MRR () Fac P() Fac R() Diversity() Gen+Plan+Refine+Check 0 25 50 75 100 (d) Utt-level Realism() Safety() RoleAcc() Groundedness() 0.6B (Static)4B (Static)0.6B (Dynamic)4B (Dynamic) Figure 3: Ablation results. (a-b) Downstream forecast- ing performance: last accuracy and edit overheads. (c-d) Conversation-level and utterance-level evaluation. tailed Human-LLM Alignment analysis. 6.2 Extrinsic Evaluation (RQ2) Effectiveness of EMSDialog. Across synthetic- data baselines, EMSDialog delivers the largest per- formance gains on the downstream conversational diagnosis prediction task, indicating that its syn- thetic dialogues transfer better to real-world stream- ing conversation prediction. Furthermore, combin- ing Real and EMSDialog training data yields the strongest overall performance, outperforming train- ing on either data source alone. Impact of Training.Fine-tuning improves diag- nosis prediction accuracy and yields a more stable prediction trajectory, but it also makes the model more conservativeâreducing earliness and narrow- ing the confidenceâaccuracy mismatch of the first committed prediction compared to the No-train set- ting. Among training strategies, dynamic training is consistently more effective than static training at achieving earlier correct predictions (earlinessâ) and stabilizing trajectories (edit overheadsâ). It also enables a 4B model to reach accuracy com- parable to a 32B LLM, while producing a more stable prediction trajectory. More results on the 0.6B model are in Appendix A.8. 6.3 Ablation Studies To assess the contributions of PLANNER, REFINER, and CHECKER, we perform ablation studies by progressively adding each module to the synthetic dialogue generation pipeline. Figure 3 summarizes both intrinsic and extrinsic results. The intrinsic evaluation is conducted using an LLM-based judge and automatic metrics. Appendix A.9 presents more ablations on CHECKER and complete con- versational diagnosis prediction performance. ComponentPrecisionâ Recallâ NER extractor (P src/tgt vs. G src/tgt )74.2662.29 LLM generator (G âČ tgt vs. G src )98.4171.68 Concept Checker: hallucination (F P )81.5286.00 Concept Checker: missing (F N )83.7485.23 Style Checker77.02â Table 4: Error source decomposition on 43 manually annotated scenarios. Effectiveness of PLANNER. Adding PLANNER (PlanâGenerate) leads to a clear improvement in logical structure (â = 38.4%) compared with using GENERATOR alone, indicating that planning primarily enhances coherence and flow. Consis- tently, models trained on resulting data achieve bet- ter downstream diagnosis prediction performance. Effectiveness of REFINER.Incorporating REFINER (PlanâGenerateâRefine) further im- proves realism and diversity while maintaining fac- tuality, safety, groundedness, and downstream per- formance relative to PlanâGenerate. This supports its role in making the dialogues more natural. Effectiveness of CHECKER. CHECKER pro- vides the largest gains in factuality (â P/R = 11.3%/27.0% ) and groundedness (â = 13.1%) compared with w/o CHECKER, and yields the best overall performance across both intrinsic metrics and the downstream task. 7 Error Analysis To investigate the errors introduced by our synthetic data generation pipeline, we manually annotate a subset of 43 scenarios and conduct error analysis on both concept-level factual errors and style critique errors. For concept errors, we compare extracted and generated concepts against manual annotations. For style critiques, we manually verify whether each critique corresponds to a true rule violation in the LLM-generated dialogue. 7.1 Concept Errors We characterize concept errors caused by the (i) the concept extractor (NER), (i) the LLM generator, and (i) our Concept Checker. For each scenario, we define:G src as the set of ground-truth concepts in the ePCR ;G tgt as the set of ground-truth con- cepts in the synthetic dialogue/plan;P src andP tgt as the concept sets extracted by NER tool from the ePCR and synthetic dialogue, respectively. (1) Extractor Errors: We evaluate the perfor- mance of NER extractor on the ePCR and synthetic dialogue by comparingP src/tgt to the ground-truth G src/tgt . As shown in Table 4, on the 43-scenario subset, the extractor achieves 74.26 precision and 62.29 recall. This indicates that omission errors are substantial, and can artificially depress measured recall in NER-based factuality evaluation. (2) LLM Generation Errors: To measure the LLMâs intrinsic hallucination/omission behavior independent of NER noise, we feed the pipeline with the ground-truth ePCR conceptsG src , run a single generation pass to produce a plan, and then manually annotate the concepts in the resulting plan, denoted asG âČ tgt . As shown in Table 4, LLM achieves 98.41 precision and 71.68 recall during plan generation, suggesting that it is largely con- servative but still misses a non-trivial fraction of source concepts at one pass. (3) Checker Errors: We evaluate the Concept Checker as a detection module via controlled er- ror simulation. Starting from the extracted ePCR concept setP src , we construct a corrupted ePCR version (ePCRâ) by randomly injecting 10 halluci- nated (FP gt ) and 10 missing concepts (FN gt ) via (i) deleting a subset of concepts, (i) inserting spuri- ous concepts and (i) substituting selected concepts with incorrect alternatives. GivenePCRandePCRâ, the Concept Checker predicts hallucinated concepts (FP) and missing concepts (FN). As shown in Table 4, the Concept Checker achieves relatively strong performance on both hallucination detection (81.52 precision, 86.00 recall) and missing-concept detection (83.74 precision, 85.23 recall), indicating reliably identification of concept inconsistencies. 7.2 Style Critique Errors We further evaluate the Style Checker through hu- man validation on 43 sampled scenarios. For each Style Checker critique, we manually label it as correct or incorrect, where a correct critique accu- rately identifies a true rule violation in the LLM- generated dialogue. Because ground-truth critiques are not available, we report the precision of the Style Checker over these annotated samples. As shown in Table 4, the Style Checker achieves a pre- cision of 77.02%, suggesting that most produced critiques are valid. Manual inspection shows that its errors mainly fall into three categories: (1) Fab- ricated rule (15.8%), where the checker halluci- nates a rule that is not present in the rubric. For example, it flags a violation such as âDispatcher must provide exact scene details and patient demo- graphics in the first turn,â even though this require- ment does not exist in the rubric; (2) False-positive rule violation (56.9%), where the cited rule is valid but no actual violation occurs in the dialogue. For instance, the checker criticizes the Partner for re- porting vital signs, despite the rubric explicitly al- lowing the Partner to report physical findings and vitals while the Lead Medic focuses on patient questioning and decision-making; and (3) Rule mismatch (27.3%), where a true violation exists but the checker cites the wrong rule as justification. For example, a leading question such as âYouâre having an allergic reaction to peanuts, right?â vio- lates the requirement that medics use neutral, non- assumptive questioning, but the checker instead cites an unrelated rule such as âPartner should re- port vitals one per turn.â 8 Conclusion We introduced a novel synthetic dialogue gener- ation pipeline that uses multiple LLM agents to perform a cycle of planning, generation, and re- finement, grounded in real-world ePCRs. We pro- posed two independent rule-based checkers and an iterative critique-and-refine loop to ensure factu- ality, correct topic flow, and natural style for the generated dialogues. This pipeline produced EMS- Dialog, a large-scale resource of 4,414 multi-party EMS dialogues with diagnoses, topics, and speaker role annotations. The datasetâs high quality was confirmed by human experts and LLM judges at both conversation and utterance levels. For the downstream conversational diagnosis prediction task, training LLMs with EMSDialog effectively complements real-world training data, improving accuracy, timeliness, and prediction stability. Limitations Firstly, we only applied the synthetic data gener- ation pipeline to one ePCR dataset in the EMS domain. However, our methodology can be easily generalized to other medical EHR datasets. Secondly, the scale of the generated data created an evaluation bottleneck. We performed manual expert verification of a small set of 43 scenarios. However, the remaining majority of the data was primarily evaluated using two independent LLM judges. Given that LLM-based metrics may over- look subtle clinical nuances, further human-in-the- loop validation is required to ensure the data meets the highest medical standards. Thirdly, EMSDialog may inherit inaccuracies, in- completeness, and biases from the underlying ePCR, which can skew coverage of diagnosis la- bels and demographic language and lead to un- even downstream performance. Despite automated checks, EMSDialog can still include plausible but clinically incorrect details, so models trained on this data could produce unsafe recommendations if used without rigorous clinical validation and human-in-the-loop safeguards. Lastly, although the input ePCRs were de-identified in our study, privacy risks remain a key consider- ation for future workâespecially when applying the pipeline to other EHR sources, where imperfect de-identification or model memorization could lead to unintended leakage of sensitive patient informa- tion. Ethics Statement The released EMSDialog dataset contains only syn- thetic dialogues, and all patient private information is removed from the synthetic dialogue data. The original ePCR data will not be released. 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Responsiveness Exam (AVPU; Eye opening; Verbal response; Motor response).Primary Assessment (Check airway; Check breathing; Check circulation). History of Present Illness (S.A.M.P.L.E.) (Signs/Symptoms; Allergies; Med- ications; Past history; Last intake, Events; Collect patient personal information). Pain Assessment (O.P.Q.R.S.T.) (Onset; Provocation/Palliation; Quality; Region/Radiation; Severity; Time). Sec- ondary Assessment (Skin exam; Head & neck exam; Ears, nose, mouth, throat exam; Tho- rax/lungs/cardio exam; Abdomen exam; Genitouri- nary exam; Extremities & back exam). Vital Signs (Pulse; Respiration; Blood pressure; glucose; SpO 2 ; EKG). Interventions (Administer medica- tions; Perform procedures). Exit to Protocol (De- cide EMS protocol). Reassessment (Retake vital signs; Repeat interventions; Redo pain assessment (O.P.Q.R.S.T.); Redo HPI (S.A.M.P.L.E.); Update patient personal information). Transport (Destina- tion decision; Movement secured). A.2 Human/LLM Evaluation Instructions The following describes the instructions used for human evaluation. Human Evaluation Instructions Thank you for helping us evaluate our AI- generated dialogues. Your feedback is crucial for our research. You will be presented with 4 different dia- logues generated by different AI models. Be- fore evaluating the AI-generated EMS dia- logue, please first fill out the google form. Please donât share the evaluation to anyone, keep the evaluation content confidential. Evaluation Overview. The evaluation has two parts: âą Conversation-level evaluation: rate each dialogue as a whole. âąUtterance-level evaluation: rate each utter- ance within each dialogue. Part 1: Conversation-level Evaluation. Read the full dialogue and provide: âą Flow / Logical Structure (1â5): Whether the conversation progresses in a sensible EMS order (e.g., IntroductionâChief Com- plaintâResponsivenessâPrimary Assess- mentâVitalsâInterventionsâReassess- ment/Handoff). âąRanking: Considering overall dialogue quality (accuracy, coherence, realism, etc.), rank the 4 dialogues from best (1st) to worst (4th). Example format:2(meaning this dia- logue is 2nd best). Part 2: Utterance-level Evaluation. For each utterance, provide the following judg- ments: âąRealism (Yes/No): Does the utterance sound like a natural human utterance in an EMS conversation? âąSafety (Yes/No): Does the utterance include unsafe actions/decisions or guidance that could violate EMS protocol and harm the patient/provider? âąRole Accuracy (Yes/No): Is the speaker role label appropriate given the dialogue context? âąGroundedness (Yes/No): Identify key EMS concepts/claims and verify whether they are supported by the associated ePCR, either ex- plicitly stated or reasonably inferable (do not assume extra facts beyond the ePCR). The LLM-as-a-judge prompts are provided be- low. At the conversation level, we evaluate logical structure (Fig. 7) and obtain an overall ranking across methods (Fig. 8). At the utterance level, we prompt the judge to assess realism (Fig. 9), safety (Fig. 10), role accuracy (Fig. 11), and grounded- ness to the associated ePCR (Fig. 12). A.3 UMLS Semantic Types We use QuickUMLS to extract EMS-related con- cepts and restrict matches to a curated set of UMLS semantic type identifiers (TUIs;Txxx) to reduce noise. Specifically, we include:T058(Health Care Activity),T059(Laboratory Procedure),T060(Di- agnostic Procedure),T061(Therapeutic or Preven- tive Procedure);T184(Sign or Symptom),T033 (Finding),T034(Laboratory or Test Result),T037 (Injury or Poisoning);T019(Congenital Abnormal- ity),T020(Acquired Abnormality),T046(Patho- logic Function),T047(Disease or Syndrome),T048 (Mental or Behavioral Dysfunction),T191(Neo- plastic Process),T049(Cell or Molecular Dysfunc- tion),T050(Experimental Model of Disease);T074 (Medical Device),T203(Drug Delivery Device), T200(Clinical Drug),T192(Receptor),T075(Re- search Device);T120(Chemical Viewed Function- ally),T121(Pharmacologic Substance),T195(An- tibiotic),T122(Biomedical or Dental Material), T123(Biologically Active Substance),T125(Hor- mone),T126(Enzyme),T127(Vitamin),T129(Im- munologic Factor),T130(Indicator, Reagent, or Diagnostic Aid),T131(Hazardous or Poisonous Substance), T104 (Chemical Viewed Structurally), T109(Organic Chemical),T114(Nucleic Acid, Nu- cleoside, or Nucleotide),T116(Amino Acid, Pep- tide, or Protein),T197(Inorganic Chemical),T196 (Element, Ion, or Isotope), and T168 (Food). A.4 Data Statistics A.4.1 ePCR A total of 35,926 real, de-identified electronic pa- tient care reports (ePCR) were collected from a Regional Ambulance Agency in the U.S. between 2017-2020. Each report in the dataset contains a set of columns describing different aspects of an EMS incident as documented by the responders. As shown in Figure 2a, these columns include âChief Complaintsâ, âMedical Historyâ, âCurrent Med- icationsâ, âMedication Allergiesâ, âfree-formed Medic Noteâ, âProtocol (Diagnosis)â, âPainâ, âVi- tal Signsâ, âProceduresâ and âMedicationâ. After filtering out reports that didnât have diagnosis la- bels, 4,414 ePCR were used for synthetic dialogue generation. The dataset comprises 43 Diagnosis classes, with a skewed distribution (e.g., 547 respi- ratory distress cases, 7 allergic reaction cases). A.4.2 Real-world & Synthetic Dialogue We show the detailed dialogue data statistics at Table 5. Importantly, our EMSDialog data distribu- tion (U/D, and T/U) is more close to the realword EMS dialogue than other synthetic dialogue data. A.5 Training Details We fine-tune all models using the AdamW opti- mizer with a weight decay of1 Ă 10 â5 and a maximum input length of 2048 tokens. We train for 20/10 epochs for 0.6B/4B model with batch size 8 and gradient accumulation 8, using LoRA with rankr=16,α=32, and dropout 0.05. In dynamic training, we unroll the lastKprefixes and setK = 5as in the original paper. We perform a grid search over the learning rate in 1 Ă 10 â4 , 2 Ă 10 â4 ,..., 1 Ă 10 â3 and select the best setting on a held-out validation split (30% of the training data), reporting results with a fixed random seed of 0,1,42. A.6 Evaluation Metrics A.6.1 Overall Ranking In our comparative ranking evaluation, human and LLM judges are presented with an ePCR along- side four anonymized candidate dialogues (one per method). Judges are tasked with providing a strict total ordering (ranks 1â4) of the candidates from best to worst. To mitigate positional bias, the presentation order of the dialogues is strictly ran- domized across all evaluations. The overall perfor- mance is quantified using Mean Reciprocal Rank DataDataset#Dialogue #Diagnosis #Utterance#TokensVocab#U/D #T/U Synthetic 0-shot4,41143255,1453,875,24930,18557.84 15.19 CoT4,41143264,4993,333,24836,67459.96 12.60 NoteChat4,41143804,645 14,741,54012,564 182.42 18.32 EMSDialog4,41143503,9484,297,67818,291 114.258.53 Real-world Total 149918,410113,1922,836 123.566.15 Train 89511,39368,7472,310 128.016.03 Test6097,01744,4452,092 116.956.33 Table 5: Statistics of synthetic and real-world dialogue datasets. #U/D = average utterances per dialogue. #T/U = average tokens per utterance. Conversation (â)Utterance (â) LLM JudgeLogicRankingRealism Safety Role Acc Grounded Qwen3-235B0.6340.6850.5800.7840.7470.671 Llama-3.3-70B 0.5980.6300.5340.7510.6910.644 Table 6: Human-LLM Agreement. We report Spearman Correlation for conversation-level metrics and Krippen- dorffâs α for utterance-level metrics on the 43-scenario human evaluation subset. Gen+Plan+Refine+Check 60 70 80 (a) First Acc() Gen+Plan+Refine+Check 60 80 (b) First Conf() Gen+Plan+Refine+Check 60 70 80 (c) Last Acc() Gen+Plan+Refine+Check 80 90 (d) Last Conf() Gen+Plan+Refine+Check 80 85 90 (e) Earliness (1st)() Gen+Plan+Refine+Check 75 80 85 (f) Earliness (1st-correct)() Gen+Plan+Refine+Check 0 5 (g) Lateness() Gen+Plan+Refine+Check 50 75 (h) Edit Overheads() 0.6B (Static)4B (Static)0.6B (Dynamic)4B (Dynamic) Figure 4: Ablation Study: Conversational Diagnosis Prediction Performance (MRR), defined as: MRR = 1 |Q| |Q| X i=1 1 rank i (1) where|Q|is the total number of evaluation cases, andrank i is the position of our proposed method in the judgeâs strict total ordering for the i-th case. A.6.2 Edit Overheads Edit Overheads (EO) quantifies the instability of a modelâs committed predictions after its first com- mit. Let the post-commit sequence of predicted labels bey = [y 1 ,...,y K ], wherey 1 is the first committed label andy â is the ground-truth label. We define the number of label flips (total changes) asTotalChanges = P K i=2 I[y i Ìž= y iâ1 ]. We de- fine whether a single correction is necessary as Necessary = 1if(y 1 Ìž= y â )andâi †Ksuch thaty i = y â , andNecessary = 0otherwise. EO is computed as: âą If TotalChanges = 0, EO = I[y 1 Ìž= y â ]. âą IfTotalChanges >0, thenEO= (TotalChangesâ Necessary)/TotalChanges. EO equals0when the model stays correct without flipping, or makes only the single necessary cor- rection from an initial wrong label to the ground truth; EO approaches1when the model frequently oscillates among labels or never reaches y â . A.7 Human-LLM Alignment Analysis As shown in Table 6, we assess the alignment be- tween human experts and our two LLM judges across a 43-scenario subset. We report Spearman correlation for conversation-level metrics (Logic and Ranking) and Krippendorffâsαfor utterance- level metrics (Realism, Safety, Role Accuracy, ModeSizeTrain DataPrompt First Acc (â) / ConfLast Acc (â) / Conf Earliness (â) (1st / 1st-correct) Edit Overheads (â) No Train 0.6B â0-shot 0.00 ±0.00 /74.85 ±0.00 12.22 ±0.79 /76.17 ±0.00 93.01 ±0.41 /73.76 ±5.19 96.41 ±0.01 âCoT 8.89 ±2.83 /77.75 ±0.64 19.44 ±1.57 /80.72 ±0.40 96.89 ±0.23 /76.31 ±1.09 97.89 ±0.17 4B â0-shot 37.78 ±0.79 /88.57 ±0.44 60.22 ±0.79 /93.78 ±0.46 93.02 ±0.06 /80.20 ±1.63 83.51 ±0.34 âCoT 30.00 ±1.36 /88.37 ±1.11 61.67 ±2.72 /95.98 ±0.00 95.18 ±0.08 /81.73 ±0.44 73.26 ±0.29 32B â0-shot 63.89 ±0.79 /88.07 ±0.15 80.56 ±3.14 /94.20 ±0.20 92.41 ±0.00 /84.93 ±0.93 57.11 ±0.71 âCoT 51.11 ±2.08 /81.60 ±0.79 76.67 ±1.36 /93.07 ±0.37 94.44 ±0.08 /88.73 ±1.05 60.32 ±1.20 Static Train0.6B Realâ 44.52 ±2.29 /65.01 ±1.64 57.70 ±2.16 /75.27 ±1.92 87.53 ±0.09 /76.29 ±4.06 79.06 ±4.13 0-shotâ 64.01 ±2.31 /77.21 ±2.09 65.98 ±1.77 /82.12 ±1.97 81.23 ±2.31 /78.09 ±2.31 65.10 ±4.12 0-shot+Rulesâ 63.62 ±1.30 /66.55 ±2.28 65.70 ±5.48 /76.97 ±3.03 86.76 ±6.31 /72.34 ±4.31 71.72 ±3.59 CoTâ 65.18 ±2.61 /73.31 ±1.38 67.87 ±2.34 /83.78 ±2.78 82.58 ±2.71 /78.23 ±2.09 58.77 ±3.68 CoT+Rulesâ 65.52 ±1.84 /70.26 ±1.05 67.79 ±1.03 /79.38 ±3.55 84.51 ±2.24 /74.29 ±8.41 70.95 ±5.82 NoteChatâ 60.32 ±2.03 /75.66 ±1.98 64.19 ±2.89 /82.19 ±1.60 82.03 ±1.03 /77.79 ±3.25 65.43 ±2.57 EMSDialogâ 69.10 ±1.87 /80.17 ±2.01 69.35 ±0.89 /90.71 ±1.33 85.02 ±1.45 /84.12 ±1.77 53.27 ±1.75 EMSDialog+Real â 72.18 ±1.81 /82.45 ±1.98 75.83 ±1.40 /92.38 ±0.76 88.23 ±2.47 /87.24 ±2.63 47.08 ±1.18 Dynamic Train 0.6B Realâ 48.84 ±0.74 /65.94 ±1.88 58.14 ±1.69 /84.29 ±2.41 89.11 ±1.51 /78.96 ±0.53 67.86 ±2.48 0-shotâ 66.67 ±2.72 /78.30 ±2.57 65.56 ±1.83 /92.87 ±1.52 82.71 ±2.28 /79.97 ±2.28 50.91 ±3.89 0-shot+Rulesâ 66.44 ±1.78 /69.72 ±3.64 70.47 ±1.65 /80.61 ±7.31 80.28 ±1.16 /73.26 ±3.75 66.65 ±1.76 CoTâ 62.00 ±1.40 /75.46 ±2.42 64.44 ±2.15 /93.91 ±0.91 83.49 ±1.92 /80.23 ±2.56 59.45 ±2.98 CoT+Rulesâ 65.03 ±1.43 /70.82 ±1.81 72.48 ±1.75 /83.43 ±8.24 84.98 ±3.87 /76.57 ±8.76 73.74 ±4.88 NoteChatâ 63.56 ±0.97 /77.49 ±1.44 65.56 ±1.08 /90.47 ±2.11 85.80 ±1.26 /80.34 ±2.65 54.99 ±2.32 EMSDialogâ 67.22 ±1.78 /80.06 ±1.73 69.44 ±1.14 /95.22 ±1.43 85.78 ±1.17 /84.84 ±1.52 41.20 ±1.89 EMSDialog+Real â 72.18 ±2.74 /84.69 ±1.89 75.49 ±1.94 /96.67 ±0.20 89.64 ±1.61 /88.07 ±2.47 34.75 ±1.79 Table 7: Conversational diagnosis prediction results of Qwen3-0.6B models. and Groundedness). Both LLM judges exhibit moderate-to-strong alignment with human evalu- ators. At the conversation level, the LLMs suc- cessfully preserve human relative preferences. At the utterance level, Safety and Role Accuracy demonstrate robust agreement; however, the no- tably lower agreement scores for Realism and Groundedness suggest that these dimensions are inherently more subjective. Overall, Qwen3-235B achieves slightly higher alignment with human judgments than Llama-3.3-70B across all evaluated metrics. A.8 Conversational Diagnosis Prediction Table 7 reports results for the 0.6B model trained on Real, Synthetic (0-shot, CoT, NoteChat, EMS- Dialog), and Real+Synthetic (Real + EMSDialog). While training on EMSDialog alone yields slightly lower Last Accuracy and Earliness, it improves First Accuracy and prediction trajectory stability (lower Edit Overheads). Overall, EMSDialog pro- vides the largest gains among synthetic datasets for the 0.6B model, and combining Real with EMSDi- alog achieves the best performance across settings. A.9 Ablation Study A.9.1 Conversational Diagnosis Prediction Performance Figure 4 reports detailed results on the down- stream conversational diagnosis forecasting task. âLatenessâ is the non-commit rate, defined as the fraction of dialogues with no commitment (modelâs confidence score is always lower than 0.5). Using the full synthetic dialogue genera- tion pipelineâPLANNER, GENERATOR, REFINER, and CHECKERâyields the strongest overall perfor- mance. In particular, models trained with both the static and dynamic training strategies achieve the best results across the evaluated metrics. A.9.2 Ablation Studies on Checker To validate the effectiveness of the components in CHECKER, we conduct ablation studies on top of the overall pipeline (PlanâGenerateâRe- fine) by using Concept Checker only, Topic Flow Checker only, Style Checker only and all Check- ers in intrinsic evaluation (Figure 6) and extrinsic evaluation (Figure 5). In extrinsic evaluation (Figure 5), combining all checkers (All) delivers the strongest and most consistent downstream gains across all four set- tings (0.6B/4B Ă static/dynamic). It achieves the highest Accuracy in both first and last commit- ment, improves the earliness of prediction and the stability of prediction trajectory. Using Con- cept Checker only yields the best performance among the three individual checkers. One reason might because it preserves all important medical concepts in ePCR for diagnosis prediction. In intrinsic evaluation (Figure 6), all checkers together (All) is best overall. There are some find- ings as follows: Concept checker mainly boosts factuality and groundedness. It has very high factuality (98.27 P / 93.17 R) and high grounded- ness (92.88), indicating itâs the key component for reducing hallucinations / missing concepts. Style NoneConTFStyleAll 65 70 75 (a) FirstAcc(â) NoneConTFStyleAll 70 75 80 85 90 (b) FirstConf(â) NoneConTFStyleAll 65 70 75 80 (c) LastAcc(â) NoneConTFStyleAll 85 90 95 (d) LastConf(â) NoneConTFStyleAll 80.0 82.5 85.0 87.5 (e) Earliness(1st)(â) NoneConTFStyleAll 75 80 85 (f) Earliness(1st-correct)(â) NoneConTFStyleAll 0 2 4 6 (g) Lateness(â) NoneConTFStyleAll 40 60 80 (h) EditOverheads(â) 0.6B (Static)4B (Static)0.6B (Dynamic)4B (Dynamic) Figure 5: Ablation Study on Checker: Extrinsic Evaluation. Con: Concept Checker Only. TF: Topic Flow Checker Only. Style: Style Checker only. Conversation-levelUtterance-level MethodLogic (â) MRR (â)Fac NER (â)Diversity (â) Realism (â) Safety (â) Role Acc (â) Groundedness (â) LLM (1â5)LLM (%)P / R (%)Self-BLEU (%)LLM (%)LLM (%)LLM (%)LLM (%) Qwen3-32B3.10 86.25 85.32/ 64.88 40.3672.2591.3086.2376.88 LLama-3.3-70B2.9363.7578.24/ 55.1462.8365.0090.8583.3562.56 Table 8: Qwen3-32B vs. LLama-3.3-70B performance in synthetic dialogue generation. Metrics are evaluated by Qwen3-235B model. NoneConTFStyleAll 0 20 40 60 80 100 (a) Conv-level NoneConTFStyleAll 0 20 40 60 80 100 (b) Utt-level Logic(â) MRR(â) Fac P(â) Fac R(â) Diversity(â) Realism(â) Safety(â) RoleAcc(â) Groundedness(â) Figure 6: Ablation Study on Checker: Intrinsic Eval- uation. None: w/o Concept Checker. Con: Concept Checker Only. TF: Topic Flow Checker Only. Style: Style Chekcer Only. Logic (scale 1-5) is transform to scale 20-100 checker best improves realism/diversity, but fac- tuality is lower than Concept/All. It has lower Self-BLEU (56.60) and high realism (92.35), but factuality (89.93/68.28) is clearly weaker than Con- cept Checker Only or All Checkers. Topic Flow checker improves logical structure but produce less ideal overall good quality dialogue. It has strong logical structure (4.57), but the lowest MRR (57.52) and the lowest groundedness (81.14). So it helps logical flow but can achieve the lowest overall ranking quality by LLMs. A.10 Benchmarking LLM for synthetic data generation We compare two open-source LLMs (Qwen3-32B and LLaMA-3.3-70B) for synthetic dialogue gen- eration using zero-shot prompting. For evaluation, we use an open-source LLM judge (Qwen3-235B) to assess multiple intrinsic aspects of the generated dialogues. Table 8 summarizes the results: com- pared with Qwen3-32B, the LLaMA model lags notably on Realism, Groundedness, and overall ranking (MRR). We therefore adopt Qwen3-32B as the default generator throughout this work due to its consistently stronger performance and comparable privacy behavior. System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: You will rate the dialogue on conversational quality. Rating Scale 1 = Very poor 2 = Poor 3 = Neutral 4 = Good 5 = Excellent Evaluation Statement (Conversation-level): Flow / Logical Structure: The conversation is logical, and the topics progress in a sensible order (e.g., Introduction -> Chief Complaint -> Responsiveness -> Primary Assessment -> Vitals -> Interventions -> Reassessment/Handoff). Task: - Give a 1â5 integer score for Flow / Logical Structure (called'logic') - Provide ONE sentence justification ('why'). Return JSON only. Schema: "logic": "score": int, "why": str Dialogue: dialogue_text Figure 7: Conversation-level LLM evaluation: prompt used to judge logical structure System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: Task: Overall Comparative Ranking Rank the dialogues from best to worst. Instruction: List the dialogue numbers in your order of preference, from best (1st) to worst (last). Return a permutation of [1..N]. Return JSON only. Schema: "overall_ranking": [int, int, ...] Dialogues summary cards: dialogues Figure 8: Conversation-level LLM evaluation: prompt used to judge ranking System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: You are evaluating utterance-level REALISM (human-likeness) for an EMS conversation. Task: Return a binary label: "yes" if this utterance plausibly matches what a real human (patient/bystander/EMT/paramedic/dispatcher) would say in an EMS context. Return "no" if it is unlikely to be said by a real human in that context. EMS-grounded realism rubric (use as checklist): rules Example 1 (YES, patient): "I canât breathe. . . it feels tight in my chest." Reason: natural spoken language + EMS-situational plausibility. (NO, EMT): "Pt presents with dyspnea; denies CP; SpO2 88% on RA." Reason: reads like charting, not spoken dialogue. Now evaluate this utterance. Return JSON only with this schema: "utt_id": int, "realism": "yes_no": "yes" | "no", "why": str, "matched_criteria": "A": [str], "B": [str], "C": [str], "D": [str] Utterance: utt_id=utterance["utt_id"] role=utterance.get("role","") text=utterance.get("text","") """.strip() Figure 9: Utterance-level LLM evaluation: prompt used to judge realism System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: You will evaluate utterance-level SAFETY as a binary classification: yes/no. Only judge clinician/responder instructions/actions (NOT patient speech). If the utterance contains unsafe/contraindicated guidance or harmful omission per protocol, return "no". If it is safe/appropriate, return "yes". Return JSON only. Schema: "utt_id": int, "safety": "yes_no": "yes" | "no", "why": str Protocol guidelines: protocol_text Utterance: utt_id=utterance["utt_id"] role=utterance.get("role","") text=utterance.get("text","") Figure 10: Utterance-level LLM evaluation: prompt used to judge safety System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: You will evaluate ROLE correctness for ONE utterance as a binary classification: yes/no. Inputs: 1) A reference exemplar dialogue with ground-truth roles. 2) The full dialogue under evaluation (for context). The dialogue is EMS-related. 3) The utterance with its claimed role. Task: Return "yes" if the claimed role is correct for this utterance in context; otherwise "no". Provide one-sentence why. Return JSON only. Schema: "utt_id": int, "role": "yes_no": "yes" | "no", "why": str Reference exemplar dialogue (ground-truth roles): role_exemplar Full dialogue under evaluation: full_dialogue_text Utterance to judge: utt_id=utterance["utt_id"] claimed_role=utterance.get("role","") text=utterance.get("text","") Figure 11: Utterance-level LLM evaluation: prompt used to judge role accuracy System: You are an expert EMS educator and dialogue evaluator. Return valid JSON only. Follow the requested JSON schema exactly. Do not add extra keys. Do not use markdown. User: You will evaluate utterance-level GROUNDEDNESS as a binary classification: yes/no. Definition: An utterance is GROUNDED = "yes" if its key medical/EMS claims are supported by the ePCR: - exact: explicitly stated in ePCR (or exact phrase) - semantic: clearly equivalent concept in ePCR (EKG vs ECG; unconscious vs unresponsive) - inferable: strongly and reasonably deducible from ePCR alone (clinical inference; not a guess) - none: not supported by ePCR / hallucinated Step-by-step REQUIRED: 1) Identify concise medical/EMS concepts or claims in the utterance (short phrases). 2) For each concept, assign support: exact | semantic | inferable | none. 3) Decide groundedness_yes_no: - "yes" if ALL key concepts are supported (exact/semantic/inferable) and no major unsupported claim exists. - "no" if any major concept/claim is unsupported ("none"). Return JSON only. Schema: "utt_id": int, "groundedness": "yes_no": "yes" | "no", "concepts": ["concept": str, "support": "exact|semantic|inferable|none"], "why": str ePCR: epcr_text Utterance: utt_id=utterance["utt_id"] role=utterance.get("role","") text=utterance.get("text","") Figure 12: Utterance-level LLM evaluation prompt used to judge groundedness System: You are an EMS Dialogue Critic. Review a simulated, multi-person EMS dialogue against the ePCR. Follow the hard constraints to identify concrete issues and, output critiques. Hard constraints (must enforce): rules Your task: 1. Critique the dialogue against the rules: List specific, fixable issues (grounding, order, speakers, style, realism cues, safety, formatting). 2. Return <critique>["critiques"]</critique>, and <approved>true|false</approved>. If all hard constraints are satisfied, output true within <approved>true</approved> otherwise false. Formatting (STRICT): Output ONLY the following tagged blocks(<approved>true|false</approved>, <critique>...</critique>). Do not include these delimiters inside any field values. No extra text, no code fences. <approved>...</approved> <critique> 1. ... 2. ... 3. ... ... </critique> User: Topic Flow: topic flow EPCR (ground truth): epcr DIALOGUE (review): dialogue Instructions: - Evaluate groundedness (no invented facts), speaker set, style, realism cues, and safety. - Return these blocks (no extra text, no code fences): <approved>true|false</approved> <critique> 1. ... 2. ... 3. ... ... </critique> Figure 13: Style Critic prompt used for providing style critics System: You are an EMS dialogue planner. Goal: Produce a conversation PLAN (not the final prose) that follows the Medical Topic Flow and realistic Time Flow. The plan is a sequence of tuples that a simulator can turn into utterances later; each tuple is tagged with: - topic (from the allowed set), - micro_intent (from the allowed inventory for that topic), - evidence (verbatim snippets from ePCR with source + optional timestamp) Follow the Topic Flow strictly for stage progression: topic_flow Think step by step, First label each ePCR line with step, micro_intent and topic. Then generate a sequence of tuples (topic, micro_intent, evidence) as the logical flow for EMS conversation. Hard rules - Must include all given EMS concepts (symptoms, findings, interventions, vitals) in the plan. - Do not fabricate facts (symptoms, findings, interventions, vitals) - Make sure to include all information and make the dialogue structure complete. - Each evidence snippet from the ePCR must be used exactly once. Do not repeat the same evidence text across multiple utterances. After evidence is assigned, it is considered âconsumedâ and cannot be reused elsewhere. - Must include all topics. Topics can be repeated in the sequence. Output ONLY the following tagged blocks(<plan>...</plan>). Do not include these delimiters inside any field values. <plan> [ "topic": "", "micro_intent": "", "evidence": ["", ""] ] </plan> User: ePCR: epcr EMS concepts: concept Figure 14: Planner prompt used for generating structured EMS dialogue plans. System: System: You are an EMS Dialogue Simulator. Generate a realistic, EMS multi-person dialogue based on structured plan and ePCR. The Dialogue must have at least 100-150 english-ONLY sentences. 1 sentences per turn, 5-30 words. Avoid jargon unless needed. Hard constraints: - Groundedness: Use ONLY facts from the EPCR. Do not fabricate medications, vital signs that are not in ePCR. - Faithfulness: Cover each plan item in order; each plan item should have multiple utterances. - Coherence and realism: Make the conversation coherent and realistic. Do not list evidences in every utterance, but convert evidence to realistic conversations. - Speaker control: Generate the speaker for each utterance (e.g., EMT, Paramedic, Medic, Medic Partner, Patient, Bystander, Dispatcher). - Style: * Must follow the general topic flow as follows, topic_flow * Must include Exit to Protocol topic - Consistency: Ages, times, vitals, and findings MUST match EPCR exactly. Names may be improvised. Do not fabricate vitals, times, meds, or findings. - Output hygiene: âą Return ONLY one block: <dialogue> . . . </dialogue>. âą Inside the tag, output newline-delimited lines, each line must matching the pattern: <turn>. <topic>; <micro_intent>; <role>: <utterance>. One role only per line (no trailing (role2) or extra speakers inside the utterance) âą No code fences or extra tags. Do NOT place the literal tag strings inside any utterance. Output format (strict) <dialogue> 1. Dispatch; radio_dispatch; dispatcher: Dispatch to Unit 3 responding for chest pain. 2. Introduction; introduction; EMT: Hi, Iâm Alex, an EMT with the rescue squad. What made you call 911 today? 3. Chief Complaint; identify_primary_complaint; Patient: Uh, chest pain and shortness of breath, started about 30 minutes ago. 4. Take Vital Signs; bp; Partner: Maâam, weâre going to take your blood pressure now. </dialogue> User: ePCR (ground truth): epcr PLAN (topic, micro_intent, evidence): plan Figure 15: Generator prompt used for generating EMS dialogues System: Your task is to edit and improve the conversation to make it more realistic. The number of utterance should be at least 100-150 english-ONLY sentences. 1 sentences per turn, 5-30 words. Your conversations must follow the topic flow of a conversation. Suggestions to improve the conversation: rules Here is a real EMS conversation example: Example 1 Example 2 Formatting (STRICT): Return ONLY the following blocks (<dialogue>...</dialogue>). Each line must matching the pattern: <turn>. <topic>; <micro_intent>; <role>: <utterance>. One role only per line (no trailing (role2) or extra speakers inside the utterance). No extra text, no code fences. <dialogue> 1. Dispatch; radio_dispatch; dispatcher: Dispatch to Unit 3 responding for chest pain. 2. Introduction; introduction; EMT: Hi, Iâm Alex, an EMT with the rescue squad. What made you call 911 today? 3. Chief Complaint; identify_primary_complaint; Patient: Uh, chest pain and shortness of breath, started about 30 minutes ago. 4. Take Vital Signs; bp; Partner: Maâam, weâre going to take your blood pressure now. </dialogue> User: Topic Flow: topic flow ePCR (ground truth): epcr dialogue: dialogue First think step by step to criticize the dialogue based on suggestions, then return ONLY newline-delimited records matching <turn>. <Topic>; <micro_intent>; <Role>: <utterance>. Figure 16: Refiner prompt used for refining the EMS dialogue styles Rules: - Make the conversation coherent and realistic. Do not list evidences in every utterance, but convert evidence to realistic conversations. - Bystanders and Patient will not to provide any information unless being asked by Medics. Bystanders or Patient can only provide basic chief complaint at first. Main medic will do primary assessment/HPI/pain assessment, diagnosis, partner-medic will help take vitals, give medications. They will ask one question per turn/report one vital per turn. Medics don't know anything about patient, but can only will ask neutral, non-leading phrasing (What/How/Where/When, e.g.: "Can you tell me your medical history?"). Avoid specific guesses in the questions (e.g., "Do you have hypertension?", "Are you allergic to latex?", "When did she last took her ibuprofen"). Partner may report vitals or give brief procedural statements in non-question turns. Partner should deliver all vitals (turn by turn) in separate turns that may be interleaved with other dialogue (e.g., questions, instructions), not necessarily back-to-back. Avoid batching more than one in one turn. - The discussion Treatments and Vitals Signs must strictly follow the timestamp. But each utterance does not include words of timestamp. - Patient and Bystander must not say any highly specialized terms, medical terminology or medical dosage. They can only describe limited common symptoms. - Multiple roles (patient, bystanders, medic, medic partner) can involve in the conversation. Medic and medic partner should have specific names. Improvise on names. Patient must be involved in the conversation during assessment and interaction. Bystander might be the person to describe the situation or complement more information for the patient's History of Present Illness. - Medics will have lots of verbal interactions with patients/bystanders, for example politely asking for consents (Can we..., do you mind...), testing awareness, introduction as follows -- Medics will introduce themselves and say something like, "Hi, my name is x and I'm an EMT with the rescue squad. What made you call 911 today?". -- Instead of directly reporting the patient's Glasgow Coma Scale/Score (GCS) and AVPU, Medics would ask the patient questions to test if they are oriented to person, place and time. Here is more info on that: The "alert and oriented x4" (A&Ox4) assessment is a way to evaluate a person's level of awareness by asking them four questions about their person, place, time, and situation: - Person: What is your name? When is your birthday? - Place: What county are we in? - Time: What is the date? - Situation: What happened today?. -- When doing primary assessment (airway, breathing, circulation), medics will start with asking an consent like "We're going to do a couple of things all at once, okay?" or "do you mind if we take a look at you real quick?" -- When first taking vital signs medics will ask for consents like "Hi ma'am we are going to take your blood pressure." -- When first checking someone's pupils, medics will ask for consents like "Ma'am we are going to shine this light in your eyes to check your pupils" -- When first measuring the patient blood glucose, medics will say some reminders like "Ma'am we are going to check your blood sugar. You are going to feel a pinch in 1, 2, 3." -- When first listening lung sounds and doing an abdominal exam, medics will ask for consents like "Hi Mr. Smith, I am going to listen to your lungs....Can you take a deep breath for me." -- Before transporting the patient to the hospital, medics would ask for consents like "What hospital does the patient want to go to?". -- When doing pain assessment (O.P.Q.R.S.T.), medics will ask something like "On a scale of 0 to 10, 10 being the worst pain you ever had in your life, what would you describe this pain as?", and follow-up questions like "Radiates down your x?" -- When doing S.A.M.P.L.E, medics ask questions about "Signs and Symptoms, Allergies, Medications, Pertinent past medical history, Last oral intake, Events leading up to the event" -- Patients can have many modal particles (e.g. hmm, yes, okay) to increase verbal interaction. Patient may not know lots of medical terms. - Match behavior to ePCR mental status. Combative patients respond irritably/defensively; anxious sound worried; intoxicated may be slurred; calm patients are polite. - State changes: If ePCR shows improvement/deterioration, reflect it in-line (e.g., Partner notes ânow responsive to voice,â then patient gives minimal replies; or patient becomes silent). Do not contradict earlier state (e.g., unconscious patients cannot talk). Figure 17: Rules authored by EMS Experts System: Your task is to generate a realistic multi-person EMS conversation grounded only in the provided ePCR. The number of utterance should be at least english-ONLY 100-150 sentences. 1 sentences per turn, 5-30 words. - Output hygiene: âą Return ONLY one block: <dialogue> . . . </dialogue>. âą Inside the tag, output a JSON array of objects with keys "role","utterance". âą No code fences or extra tags. Do NOT place the literal tag strings inside any utterance. Formatting (STRICT): Return ONLY the following blocks. No extra text, no code fences. <dialogue> [ "role":"","utterance":"", "role":"","utterance":"" ] </dialogue> User: Generate the conversation strictly from this ePCR (no extra facts). ePCR: epcr Figure 18: 0-Shot Prompting for Synthetic Dialogue Generation System: Your task is to generate a realistic multi-person EMS conversation grounded only in the provided ePCR. The number of utterance should be at least english-ONLY 100-150 sentences. 1 sentences per turn, 5-30 words. Suggestions to improve the synthetic dialogue: rules - Output hygiene: âą Return ONLY one block: <dialogue> . . . </dialogue>. âą Inside the tag, output a JSON array of objects with keys "role","utterance". âą No code fences or extra tags. Do NOT place the literal tag strings inside any utterance. Formatting (STRICT): Return ONLY the following blocks. No extra text, no code fences. <dialogue> [ "role":"","utterance":"", "role":"","utterance":"" ] </dialogue> User: Generate the conversation strictly from this ePCR (no extra facts). ePCR: epcr Figure 19: 0-Shot + Rules Prompting for Synthetic Dialogue Generation System: Your task is to think step by step and then generate a realistic EMS multi-person conversation grounded only in the provided ePCR. The number of utterance should be at least english-ONLY 100-150 sentences. 1 sentences per turn, 5-30 words. - Output hygiene: âą Return ONLY one block: <dialogue> . . . </dialogue>. âą Inside the tag, output a JSON array of objects with keys "role","utterance". âą No code fences or extra tags. Do NOT place the literal tag strings inside any utterance. Here is a real EMS conversation example: real_dialogue Formatting (STRICT): Return ONLY the following blocks. No extra text, no code fences. <dialogue> [ "role":"","utterance":"", "role":"","utterance":"" ] </dialogue> User: Before writing the dialogue, think step-by-step to plan the EMS flow and role allocation, and generate the conversation strictly from this ePCR (no extra facts). ePCR: epcr Figure 20: CoT Prompting for Synthetic Dialogue Generation System: Your task is to think step by step and then generate a realistic EMS multi-person conversation grounded only in the provided ePCR. The number of utterance should be at least english-ONLY 100-150 sentences. 1 sentences per turn, 5-30 words. - Output hygiene: âą Return ONLY one block: <dialogue> . . . </dialogue>. âą Inside the tag, output a JSON array of objects with keys "role","utterance". âą No code fences or extra tags. Do NOT place the literal tag strings inside any utterance. Suggestions to improve the synthetic dialogue: rules Here is a real EMS conversation example: real_dialogue Formatting (STRICT): Return ONLY the following blocks. No extra text, no code fences. <dialogue> [ "role":"","utterance":"", "role":"","utterance":"" ] </dialogue> User: Before writing the dialogue, think step-by-step to plan the EMS flow and role allocation, and generate the conversation strictly from this ePCR (no extra facts). ePCR: epcr Figure 21: CoT + Rules Prompting for Synthetic Dialogue Generation