Clearer Governmental Communication: Text Simplification with ChatGPT Evaluated through Quantitative and Qualitative Research

This study explores the use of ChatGPT for simplifying Dutch government letters to improve their comprehensibility while preserving legal accuracy. We employed a three-stage mixed-methods evaluation approach to assess the effectiveness of a naive baseline, RoBERTa, and ChatGPT in simplifying six of the most complex letters selected from a corpus of 200. The evaluation process involved comparing the outputs using four metrics (ROUGE, BLEU, BLEURT, and LiNT), followed by reviews from legal and linguistic experts, and culminating in a randomized controlled trial with 72 participants to test comprehension. Our results indicate that ChatGPT substantially enhances the comprehension of government letters, evidenced by more than a 20% increase in comprehensibility scores and a 19% improvement in participants’ ability to correctly answer questions related to follow-up actions based on the simplified texts. Additionally, our study underscores the importance of a thorough evaluation framework and advises caution in solely depending on automated metrics for assessing text simplification.