Report on the 5th Workshop on Reducing Online Misinformation through Credible Information Retrieval (ROMCIR 2025) at ECIR 2025

The 5th Workshop on Reducing Online Misinformation through Credible Information Retrieval (ROMCIR 2025) was held as part of the Satellite Events of the 47th European Conference on Information Retrieval (ECIR 2025). The Workshop provided a vibrant forum for researchers and practitioners to discuss innovative methods for improving access to accurate information and tackling the widespread issue of information disorder in the contemporary digital landscape. The challenge of online misinformation is inherently multifaceted. It spans a broad spectrum of information sources—including Websites, social media posts, and automatically generated content—and cuts across diverse platforms and domains. These include, but are not limited to, fake news detection, retrieval of trustworthy content—particularly in the health domain—and techniques for reducing the spread of propaganda. A particularly timely theme that gained prominence in this edition of ROMCIR was the growing influence of generative AI models, such as Large Language Models (LLMs). Discussions began to highlight both the risks posed by LLMs in unintentionally amplifying misinformation, and their potential to enhance Information Retrieval Systems (IRSs) when properly guided and constrained. Within this rich and evolving context, a variety of approaches to the challenge of accessing truthful and verifiable information were explored. The keynote speech and the research contributions presented at this year's Workshop primarily focused on several key themes: the use of crowdsourcing to mitigate misinformation; the interplay between misinformation and LLMs, in particular related to fact-checking and rumor verification; and the societal implications of misinformation, particularly its impact on children. Date: 10 April 2025. Website: https://romcir.disco.unimib.it/.