Ibrahim Baroud
2026
Developing Annotation Guidelines for CSAM Prevention Interventions: Psychosocial Risk and Protective Factors Grounded in Research and Clinical Practice
Vera Czehmann | Christine Hovhannisyan | Lena Elisabeth Hoffmann | Paula Busch | Ibrahim Baroud | Sebastian Möller | Roland Roller | Hannes Gieseler | Lisa Raithel
Proceedings of the Sixth Resources and ProcessIng of linguistic, para-linguistic and extra-linguistic Data from people with various forms of cognitive/psychiatric/developmental impairments in cooperation with the MENTAL.ai consortium
Vera Czehmann | Christine Hovhannisyan | Lena Elisabeth Hoffmann | Paula Busch | Ibrahim Baroud | Sebastian Möller | Roland Roller | Hannes Gieseler | Lisa Raithel
Proceedings of the Sixth Resources and ProcessIng of linguistic, para-linguistic and extra-linguistic Data from people with various forms of cognitive/psychiatric/developmental impairments in cooperation with the MENTAL.ai consortium
This work discusses sexual offending, specifically child sexual abuse material (CSAM), in the context of prevention. We introduce a domain-specific, span-level annotation scheme and guidelines to identify psychosocial risk and protective factors in therapist-led, anonymous chat interventions with voluntarily help-seeking individuals concerned about their pedophilic interests and the risk of CSAM use. The scheme is grounded in previous research and clinical experience, and intended for within-intervention guidance and longitudinal tracking, rather than actuarial risk scoring. Annotating a pilot subset (8 clients, 31 sessions), inter-annotator agreement was moderate but improved after calibration, which is consistent with the linguistic and clinical ambivalence present in the data. We track a session-wise Protective Ratio, i.e., the share of protective factors among all coded factors, and examine its behaviour over time during the intervention and around self-reported relapse within clients. In exploratory automation, LLM-based span extraction outperforms BERT baselines but overall performance remains limited by small data and mixed-evidence spans. While complete anonymisation of the corpus is in progress, we release the label scheme, guidelines, and non-sensitive artefacts of our analyses.
MultiGraSCCo: A Multilingual Anonymization Benchmark with Annotations of Personal Identifiers
Ibrahim Baroud | Christoph Otto | Vera Czehmann | Christine Hovhannisyan | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Ibrahim Baroud | Christoph Otto | Vera Czehmann | Christine Hovhannisyan | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Fifteenth Language Resources and Evaluation Conference
Accessing sensitive patient data for machine learning is challenging due to privacy concerns. Datasets with annotations of personally identifiable information are crucial for developing and testing anonymization systems, which would enable safe data sharing that complies with privacy regulations. Since accessing real patient data is a bottleneck, synthetic data offers an efficient solution for data scarcity, bypassing privacy regulations that apply to real data. Moreover, neural machine translation can help to create high-quality data for low-resource languages by translating validated real or synthetic data from a high-resource language. In this work, we create a multilingual anonymization benchmark in ten languages, using a machine translation methodology that preserves the original annotations and renders city and people names in a culturally and contextually appropriate form in each target language. Our evaluation study with medical professionals confirms the quality of the translations, both in general and with respect to the translation and adaptation of personal information. Our benchmark with over 2,500 annotations of personal information can be used in many applications, including training annotators, validating annotations across institutions without legal complications, and helping improve the performance of automatic personal information detection. We make our benchmark and annotation guidelines available for further research.
Evaluating Encoder- and LLM-Based Approaches for Robust Indirect Personal Identifier Detection
Christoph Otto | Ibrahim Baroud | Akiko Aizawa | Sebastian Möller | Roland Roller | Lisa Raithel
Proceedings of the Joint Workshop on Legal and Ethical Issues in Human Language Technologies and Computational Approaches to Language Data Pseudonymization, Anonymization, De-identification, and Data Privacy (LEGAL2026 and CALD-pseudo 2026) @ LREC 2026
Christoph Otto | Ibrahim Baroud | Akiko Aizawa | Sebastian Möller | Roland Roller | Lisa Raithel
Proceedings of the Joint Workshop on Legal and Ethical Issues in Human Language Technologies and Computational Approaches to Language Data Pseudonymization, Anonymization, De-identification, and Data Privacy (LEGAL2026 and CALD-pseudo 2026) @ LREC 2026
Removing explicit protected health information does not fully eliminate re-identification risk in clinical text. Contextual attributes such as socio-economic status, institutional affiliations or detailed life circumstances may still enable linkage attacks. These heterogeneous and sparsely distributed elements, termed Indirect Personal Identifiers, extend de-identification beyond fixed identifier lists and pose new modeling challenges. Therefore, we present the first systematic comparison of encoder-only models, prompt-based LLMs and hybrid pipelines for span-level IPI detection in English discharge summaries. A fine-tuned RoBERTa-large model improves on an existing baseline and substantially outperforms ChatGPT-5.2, achieving 0.906 micro-F1 and 0.724 macro-F1, compared to 0.509 micro-F1 and 0.487 macro-F1. Our findings indicate that IPI detection constitutes a distinct modeling regime characterized by class imbalance and high intra-class variability, where scaling model capacity alone does not guarantee macro-level robustness. We show that supervised encoder models currently provide the most reliable foundation for extending anonymization guarantees and future research.
2025
Beyond De-Identification: A Structured Approach for Defining and Detecting Indirect Identifiers in Medical Texts
Ibrahim Baroud | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Sixth Workshop on Privacy in Natural Language Processing
Ibrahim Baroud | Lisa Raithel | Sebastian Möller | Roland Roller
Proceedings of the Sixth Workshop on Privacy in Natural Language Processing
Sharing sensitive texts for scientific purposes requires appropriate techniques to protect the privacy of patients and healthcare personnel. Anonymizing textual data is particularly challenging due to the presence of diverse unstructured direct and indirect identifiers. To mitigate the risk of re-identification, this work introduces a schema of nine categories of indirect identifiers designed to account for different potential adversaries, including acquaintances, family members and medical staff. Using this schema, we annotate 100 MIMIC-III discharge summaries and propose baseline models for identifying indirect identifiers. We will release the annotation guidelines, annotation spans (6,199 annotations in total) and the corresponding MIMIC-III document IDs to support further research in this area.
RecordTwin: Towards Creating Safe Synthetic Clinical Corpora
Seiji Shimizu | Ibrahim Baroud | Lisa Raithel | Shuntaro Yada | Shoko Wakamiya | Eiji Aramaki
Findings of the Association for Computational Linguistics: ACL 2025
Seiji Shimizu | Ibrahim Baroud | Lisa Raithel | Shuntaro Yada | Shoko Wakamiya | Eiji Aramaki
Findings of the Association for Computational Linguistics: ACL 2025
The scarcity of publicly available clinical corpora hinders developing and applying NLP tools in clinical research. While existing work tackles this issue by utilizing generative models to create high-quality synthetic corpora, their methods require learning from the original in-hospital clinical documents, turning them unfeasible in practice. To address this problem, we introduce RecordTwin, a novel synthetic corpus creation method designed to generate synthetic documents from anonymized clinical entities. In this method, we first extract and anonymize entities from in-hospital documents to ensure the information contained in the synthetic corpus is restricted. Then, we use a large language model to fill the context between anonymized entities. To do so, we use a small, privacy-preserving subset of the original documents to mimic their formatting and writing style. This approach only requires anonymized entities and a small subset of original documents in the generation process, making it more feasible in practice. To evaluate the synthetic corpus created with our method, we conduct a proof-of-concept study using a publicly available clinical database. Our results demonstrate that the synthetic corpus has a utility comparable to the original data and a safety advantage over baselines, highlighting the potential of RecordTwin for privacy-preserving synthetic corpus creation.