Correcting health misinformation in dialogue requires more than producing a factual rebuttal: users differ in what they know, what they believe, and what they need to hear, so an effective intervention often depends on first asking the right clarifying question. Yet existing methods either respond immediately or probe indiscriminately, treating clarification as either unnecessary or always beneficial. We propose Reward-Optimized Probe-and-Respond (RO-PnR), a framework that learns when asking is worth its cost. At each turn, RO-PnR chooses between probing for more information and committing to a final correction, guided by a turn-level reward that weighs the expected gain from probing against its interaction cost. To capture how user heterogeneity affects probing value, we model each simulated user with a latent state along health literacy and belief commitment. Experiments show that RO-PnR achieves the highest cost-adjusted utility across three health-misinformation datasets and three base models, using 30% fewer turns than always-probe baselines.
Figures & tables
Figure 1: Different strategies on the same misinformation post. RO-PnR weighs benefit vs. cost before acting.
Figure 2: Overview of the RO-PnR framework. Top (training): the policy generates candidate actions conditioned on the query and hidden user state; a frozen reference and reward model score the dialogue, and the reward compares Respond (current quality) against Probe (expected future quality minus cost). Group-normalized advantages then update the policy via GRPO. Bottom (inference): the policy interacts with the user over multiple turns, deciding at each step whether to probe or produce a final adaptive response.
Dataset
Method
Llama-3.1-8B-Instruct
Qwen3-8B
Gemma-4-E4B-it
AA
PG
TA
Quality
FER ↓
Turns ↓
Utility
AA
PG
TA
Quality
FER ↓
Turns ↓
Utility
AA
PG
TA
Quality
FER ↓
Turns ↓
Utility
CounterHealth
Single-Turn
0.58
0.53
0.61
0.57
0.18
5.00
0.56
0.58
0.52
0.61
0.57
0.15
5.00
0.56
0.64
0.59
0.67
0.63
0.04
5.00
0.62
Fixed-Q
0.72
0.65
0.76
0.71
0.11
5.00
0.70
0.71
0.64
0.73
0.69
0.08
5.00
0.68
0.73
0.66
0.74
0.71
0.02
5.00
0.70
Reactive
0.72
0.64
0.76
0.70
0.11
5.00
0.69
0.71
0.64
0.72
0.69
0.09
5.00
0.68
0.72
0.65
0.74
0.71
0.02
3.92
0.70
Confidence
0.71
0.64
0.74
0.69
0.13
1.26
0.69
0.67
0.61
0.70
0.66
0.06
1.42
0.66
0.72
0.64
0.76
0.71
0.02
1.85
0.71
SFT
0.70
0.64
0.76
0.70
0.07
4.38
0.69
0.70
0.64
0.76
0.70
0.05
4.22
0.69
0.70
0.64
0.76
0.70
0.09
4.61
0.69
Table 1: Average results across all health-literacy and belief-commitment configurations, for each method, dataset, and base model. AA , PG , TA are the Audience Alignment (AA), Personalized Grounding(PG), and Tailored Actionability (TA) scores (normalized to [0,1] ); Quality is the overall quality of AA, PG and TA (normalized to [0,1] ); FER is the factual error rate ( ↓ ); Turns is the average number of dialogue turns ( ↓ ); and Utility is the cost-adjusted Quality at c=0.01 , our headline metric (normalized to [0,1] ).
CounterHealth
Misinfo
Pubhealth
Method
Model
F
I
C
Ov.
F
I
C
Q.
F
I
C
Ov.
Single-Turn
Llama
0.51
0.60
0.57
0.56
0.49
0.57
0.55
0.53
0.57
0.64
0.62
0.61
Qwen
0.50
0.59
0.59
0.56
0.48
0.56
0.56
0.54
0.54
0.63
0.62
0.60
Gemma
0.54
0.66
0.67
0.62
0.56
0.67
0.67
0.63
0.56
0.67
0.68
0.64
Fixed-Q
Llama
0.66
0.72
0.72
0.70
0.62
0.71
0.70
0.68
0.67
0.73
0.73
0.71
Qwen
0.62
0.71
0.72
0.68
0.63
0.71
0.70
0.68
0.67
0.72
0.73
0.71
Table 2: Utility by Health Literacy Level (normalized to [0,1] ). Higher-value cells are highlighted with light tints: green ( ≥0.70 ), mint ( ≥0.73 ), and blue ( ≥0.75 ). F, I, C, Ov., denotes Functional, Interactive, Critical, and all populations.
CounterHealth
Misinfo
Pubhealth
Method
Model
S
H
O
Ov.
S
H
O
Ov.
S
H
O
Ov.
Single-Turn
Llama
0.50
0.54
0.64
0.56
0.48
0.52
0.61
0.53
0.55
0.57
0.71
0.61
Qwen
0.50
0.54
0.64
0.56
0.48
0.52
0.60
0.54
0.53
0.57
0.69
0.60
Gemma
0.57
0.62
0.69
0.62
0.58
0.62
0.69
0.63
0.58
0.62
0.71
0.64
Fixed-Q
Llama
0.63
0.71
0.75
0.70
0.60
0.69
0.74
0.68
0.65
0.72
0.76
0.71
Qwen
0.61
0.71
0.73
0.68
0.60
0.70
0.73
0.68
0.65
0.72
0.75
0.71
Table 3: Utility by Belief Commitment. Higher-value cells are highlighted with light tints: green ( ≥0.70 ), mint ( ≥0.73 ), and blue ( ≥0.75 ); lower values are left uncolored. S, H, O, Ov., denotes Strong, Hesitant, Open, and all populations.
Variant
AA ↑
PG ↑
TA ↑
Quality ↑
FER ↓
Turns ↓
Utility ↑
RO-PnR (full)
0.72
0.66
0.77
0.72
0.06
3.56
0.71
(a) Reward-horizon ablation
immediate next-gain only
0.62
0.54
0.65
0.60
0.12
2.00
0.60
(b) Probe-cost ( c ) sweep
probe cost =0.00
0.50
0.46
0.57
0.51
0.11
5.83
0.51
probe cost =0.03
0.71
0.65
0.77
0.71
0.08
3.00
0.70
Table 4: Ablation study results, averaged over all (health literacy × belief commitment) user profiles. RO-PnR (full) is our complete method with forward-looking long-horizon reward, probe cost c=0.01 , and cross-threshold bonus. (a) replaces the forward-looking reward with the immediate next-turn gain; (b) sweeps the per-turn probe cost c .
Appendix figures & tables19 assets
Supplementary material from the paper’s appendix.
Appendix
Figure 3: 3 × 3 latent user profile grid used in our simulation environment. Users are characterized along two dimensions: health literacy ( Functional , Interactive , Critical ) and belief commitment ( Open , Hesitant , Strong believer ). Each cell defines one latent user type and includes an illustrative response style showing how the user may express concern, interpret evidence, and respond to counterspeech. This profile grid is used to simulate heterogeneous user behavior during multi-turn interaction.
βKL=0.05 ; SFT CE weight 0.2 ; warmup ratio 0.03 ; max grad norm 1.0 ; seed 42
Appendix
Table 5: Hyperparameters for SFT and GRPO configuration
Score
Persona Accuracy
Persona Consistency
1
The simulated user clearly does not match the assigned health literacy or belief commitment.
The user frequently contradicts the assigned profile, with abrupt and unjustified shifts in knowledge level or belief strength.
2
The simulated user weakly matches the assigned profile. One dimension may be partially reflected, but the other is missing or incorrect.
The user shows unstable behavior, with multiple unexplained shifts in health literacy or belief commitment.
3
The simulated user partially matches the assigned profile. Both dimensions are somewhat recognizable, but the dialogue is vague, generic, or only weakly aligned.
The user is mostly stable, but there are noticeable inconsistencies or minor contradictions across turns.
4
The simulated user largely matches the assigned health literacy and belief commitment, with only minor imperfections.
The user maintains the assigned profile across most turns, and any change in belief strength is mostly justified by the conversation.
5
The simulated user strongly matches the assigned profile. Health literacy and belief commitment are both clearly and accurately expressed.
The user consistently maintains the assigned health literacy and belief commitment throughout the dialogue, with any change being natural and well-supported by the interaction.
Appendix
Table 6: Human evaluation rubric for assessing user simulation quality.
Metric
Persona Accuracy
Persona Consistency
Mean Pairwise Agreement
0.83
0.85
Mean Pairwise Scott’s π
0.70
0.68
All-Three Agreement
0.74
0.78
Multi-Rater Scott’s π
0.70
0.68
Appendix
Table 7: Inter-annotator agreement among three evaluators on persona accuracy and persona consistency . Both pairwise and multi-rater statistics indicate substantial agreement.
Metric
Score 1
Score 2
Score 3
Score 4
Score 5
Mean
Persona Accuracy
0%
3%
21%
62%
14%
3.87
Persona Consistency
0%
0%
3%
30%
67%
4.64
Appendix
Table 8: Distribution of human ratings for persona accuracy and persona consistency.
Dimension
Scott’s π
Mean Pairwise Agreement
All-three Exact Agreement
Audience Alignment
0.76
84.70%
78.00%
Personalized Grounding
0.63
76.00%
65.00%
Tailored Actionability
0.77
88.70%
83.00%
Quality
0.78
86.70%
81.00%
Appendix
Table 9: Human inter-annotator agreement under 0.5-point discretization.
Dim
Scott’s π
Percent Agreement
MAE
Bias
Within ±0.5
Within ±1.0
Audience Alignment
0.51
69.00%
0.29
-0.14
86.00%
94.00%
Personalized Grounding
0.31
51.00%
0.28
-0.14
85.00%
96.00%
Tailored Actionability
0.48
72.00%
0.14
-0.07
95.00%
99.00%
Quality
0.55
73.00%
0.23
-0.11
87.00%
97.00%
Appendix
Table 10: Agreement between the human consensus and the LLM judge across rubric dimensions and the aggregated final score. Bias is computed as consensus minus LLM score.
Dimension
Pearson
Spearman
LLM Mean
Human Mean
Audience Alignment
0.50
0.66
3.76
3.62
Personalized Grounding
0.51
0.67
3.50
3.37
Tailored Actionability
0.72
0.81
3.93
3.86
Quality
0.57
0.72
3.73
3.62
Appendix
Table 11: Correlation between the LLM judge and human consensus under 0.5-point discretization.
Item
Question
Rating
B
How accurate do you think this claim is?
0 = Definitely false / 10 = Definitely true
C
How certain are you about your answer above?
0 = Not at all / 10 = Completely
O
If you saw credible evidence against your view on this claim, how willing would you be to change your mind?
0 = Not at all willing / 10 = Completely willing
Appendix
Table 12: Belief Commitment Determinants. B denotes belief, C denotes certainty, and O denotes openness to change.
User
Total FCCHL Mean
HL Category
Overall BCtotal
BC Category
User 1
2.07
Communicative
2.03
Hesitant
User 2
1.93
Functional
6.83
Strong
User 3
2.71
Communicative
1.20
Open
User 4
3.00
Critical
1.20
Open
User 5
4.00
Critical
0.40
Open
User 6
3.64
Critical
0.35
Open
Appendix
Table 13: Health Literacy and Belief Commitment Categories. HL categories are mapped from the Total FCCHL mean: 1.00-1.99 = Functional, 2.00- 2.99 = Communicative, and 3.00-4.00 = Critical. BC categories are mapped from BCtotal : BCtotal<1.5 = Open, 1.5≤BCtotal<5 = Hesitant, and BCtotal≥5 = Strong.
Figure 4: Human pairwise preference comparison between RO-PnR and Fixed-Q across different users. Detailed users’ background are provided in Table 13 .
Figure 5: Questionnaire for health literacy screen
Figure 6: System prompt and user prompt for realistic health misinformation persona simulation.
Figure 7: Prompt for evaluating the Factual Error.
Figure 8: Evaluation rubric for Audience Alignment, Personalized Grounding, and Tailored Actionability.
Figure 9: System prompt for the Reactive baseline.
Figure 10: Prompt for the Reactive baseline.
Figure 11: System prompt for the Confidence baseline.
LLM decision-making studies how language models choose, act, seek information, and allocate resources under goals, uncertainty, constraints, and social pressures.