Title: Visual Authority and the Rhetoric of Health Misinformation: A Multimodal Analysis of Social Media Videos Show Chinese title

Title: 视觉权威与健康错误信息的修辞：社交媒体视频的多模态分析

Abstract: Short form video platforms are central sites for health advice, where alternative narratives mix useful, misleading, and harmful content. Rather than adjudicating truth, this study examines how credibility is packaged in nutrition and supplement videos by analyzing the intersection of authority signals, narrative techniques, and monetization. We assemble a cross platform corpus of 152 public videos from TikTok, Instagram, and YouTube and annotate each on 26 features spanning visual authority, presenter attributes, narrative strategies, and engagement cues. A transparent annotation pipeline integrates automatic speech recognition, principled frame selection, and a multimodal model, with human verification on a stratified subsample showing strong agreement. Descriptively, a confident single presenter in studio or home settings dominates, and clinical contexts are rare. Analytically, authority cues such as titles, slides and charts, and certificates frequently occur with persuasive elements including jargon, references, fear or urgency, critiques of mainstream medicine, and conspiracies, and with monetization including sales links and calls to subscribe. References and science like visuals often travel with emotive and oppositional narratives rather than signaling restraint. Show Chinese abstract

Abstract: 短视频平台是健康建议的核心场所，其中混合了有益的、误导性的和有害的内容。 本研究不评判真实性，而是通过分析权威信号、叙述技巧和盈利模式的交集，探讨营养和补充剂视频中可信度的呈现方式。 我们收集了来自TikTok、Instagram和YouTube的152个公开视频组成的跨平台语料库，并对每个视频的26个特征进行标注，涵盖视觉权威性、演讲者属性、叙述策略和互动提示。 一个透明的标注流程结合了自动语音识别、有原则的帧选择和多模态模型，通过对分层子样本的人工验证显示出高度一致性。 描述性分析显示，自信的单个演讲者在工作室或家庭环境中占主导地位，而临床情境很少见。 分析上，权威线索如头衔、幻灯片和图表、证书经常与说服性元素如专业术语、引用、恐惧或紧迫感、对主流医学的批评和阴谋论一起出现，并与盈利手段如销售链接和订阅呼吁一起出现。 引用和科学类视觉内容通常伴随着情感化和对立的叙述，而不是表现出克制。