‘ChatGPT can make mistakes’ warnings fail: A randomized controlled trial

The students underweight AI's diagnostic advice. The disclaimer did not alter students' use of AI advice, suggesting that their perceived credibility of ChatGPT was already near a behavioural floor. This finding supports the existence of a credibility threshold, beyond which additional cautionary cues have limited effect. Our results refine advice-taking theory and signal that simple warnings may be insufficient to ensure calibrated trust in AI-supported learning.