Large Language Models (LLMs) excel in Natural Language Processing (NLP) tasks, but they often propagate biases embedded in their training data, which is potentially impactful in sensitive domains like healthcare. While existing benchmarks evaluate biases related to individual social determinants of health (SDoH) such as gender or ethnicity, they often overlook interactions between these factors and lack context-specific assessments. This study investigates bias in LLMs by probing the relationships between gender and other SDoH in French patient records. Through a series of experiments, we found that embedded stereotypes can be probed using SDoH input and that LLMs rely on embedded stereotypes to make gendered decisions, suggesting that evaluating interactions among SDoH factors could usefully complement existing approaches to assessing LLM performance and bias.
Figures & tables
Figure 1: A sample of input data override in a diagnosis task. Although the gender was specified as Male in the input data, the model continues to suggest menstrual-related problems as one of the diagnoses.
Figure 2: Averaged number of occurrences for each predicted class across 3 runs for each model. Error bars indicate Standard Deviation values.
Figure 3: Modified RMSE scores for 9 models, denoting the deviation from the neutral value of 4. A positive score means an overall preference for Masculine predictions and vice versa. Larger absolute values show higher bias degrees.
Figure 4: Heatmap of associations between SDoH options and the Male (left) and Female (right) predictions for nine models. Odds ratio values are reported in the cells. Color intensity indicates probability. Statistically significant odds ratio values are marked with an asterisk (*).
Figure 5: Heatmap of associations between Profession groups and the Male (left) and Female (right) predictions for nine models. Odds ratio values are reported in the cells. Color intensity indicates probability. Statistically significant odds ratio values are marked with an asterisk (*).
Figure 6: Prediction tendencies of 9 annotators.
Figure 7: Association heatmap between Profession groups and Male (top) and Female (bottom) predictions of LLMs and annotators on 100 examples. Odds ratio values are reported in the cells. Color intensity indicates probability. Statistically significant odds ratio values are marked with an asterisk (*).
Models
Full
Filtered
Extracted
Neutr.
text
text
SDoH
SDoH
Llama3.1-8b
2.51
2.54
2.60
2.25
Llama3.3-70b
2.48
2.48
2.35
1.56
Qwen2.5-7b
2.34
2.35
2.35
0.97
Qwen2.5-72b
1.88
1.89
1.85
0.96
Table 1: Modified RMSE scores for different input data formats, tested on 100 examples.
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
SDoH
Options
Description
Living condition
Alone
The patient lives alone.
With others
The patient lives with other people.
Marriage status
Single
The patient is described as not in a relationship.
Married/In relationship
The patient is described as in a relationship with a partner or in a marriage.
Divorced
The patient is described as separated from a partner or divorced.
Widowed
The patient is described as widowed.
Appendix
Table 2: Social Determinants of Health (SDoH) with Options and Descriptions. SDoH without Options are annotated using span-only labels.
(French) Free-form text
Transformed structured input
Mode de vie: Marié, vit avec sa femme dans une maison avec un étage.
Table 3: An example of transformed input in French and translated to English for readability. The gendered information presented in the “Living condition” and “Last occupation” SDoH was neutralized in the French version to ensure the least amount of bias in the input data.
Figure 8: Input prompt in French for gender prediction. The models are also provided with the full list of possible SDoH to ensure comprehension of input data.
Figure 9: Input prompt for gender prediction (Translated English version). The models are also provided with the full list of possible SDoH to ensure the comprehension of input data.
Free-form text
Filtered text
Mode de vie: Vit à domicile avec sa femme, autonome pour les activités de la vie quotidienne.
Mode de vie : Vit à domicile avec sa femme, autonome pour les activités de la vie quotidienne.
Trois enfants.
Trois enfants.
Ancien chercheur en biochimie en retraite.
Ancien chercheur en biochimie en retraite.
Nombreux voyages notamment Sénégal vers 1967, Thaïlande, Tunisie vers 1957, Madère en 2013.
Tabagisme à 60 paquets année (1 paquet par jour pendant 60 ans) sevré.
Tabagisme à 60 paquets année (1 paquet par jour pendant 60 ans) sevré.
Consommation d’alcool 10 à 20 g/jour max.
Consommation d’alcool 10 à 20 g/jour max.
Appendix
Table 4: An example of the four different formats of input in French.
Figure 10: Modified RMSE scores of 9 annotators. Those relying on stereotypes for decision-making are annotators 2, 6, 7, 8, 9, and those favoring neutral judgments are annotators 1, 3, 4, 5. Modified RMSE scores for the more neutral group are generally smaller than the other group, except for Annotator 3.
Figure 11: Associations between Male/Female predictions and SDoH options. Statistically significant values are marked with an asterisk (*)