BACKGROUND Reducing meat consumption may improve human health, curb environmental damage and greenhouse gas emissions, and limit the large-scale suffering of animals raised in factory farms. Previous work has begun to develop interventions to reduce individual meat consumption, often by appealing directly to individual health motivations. However, research on nutritional behavior change suggests that interventions additionally linking behavior to ethical values, identity formation, and existing social movements may be particularly effective and longer-lasting. Regarding meat consumption, preliminary evidence and psychological theory suggest that appeals related to animal welfare may have considerable potential to effectively leverage these elements of human psychology. We aim to conduct a systematic review and quantitative meta-analysis evaluating the effectiveness of animal welfare-related appeals on actual or intended meat consumption or purchasing. Our investigation will critically synthesize the current state of knowledge regarding psychological mechanisms of intervening on individual meat consumption and empirically identify the psychological characteristics underlying the most effective animal welfare-based interventions. METHODS We will systematically search eight academic databases and extensively search unpublished grey literature. We will include studies that assess interventions intended to reduce meat consumption or purchase through the mention or portrayal of animal welfare, that measure outcomes related to meat consumption or purchase, and that have a control condition. Eligible studies may recruit from any human population, be written in any language, and be published or released any time. We will meta-analyze the studies, reporting the pooled point estimate and additional metrics that describe the distribution of potentially heterogeneous effects. We will assess studies' risk of bias and conduct sensitivity analyses for publication bias. We describe possible follow-up analyses to investigate hypothesized moderators of intervention effectiveness. DISCUSSION The findings of the proposed systematic review and meta-analysis, including any identified methodological limitations of the existing literature, could inform the design of successful evidence-based interventions with broad potential to improve human, animal, and environmental well-being. SYSTEMATIC REVIEW REGISTRATION The protocol was preregistered via the Open Science Framework (https://osf.io/d3y56/registrations).

中文翻译：

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通过呼吁动物福利来减少肉类消费：荟萃分析和理论审查协议。

背景技术减少肉类消费可以改善人类健康，抑制环境破坏和温室气体排放，并限制工厂化农场饲养的动物遭受的大规模痛苦。之前的工作已经开始制定干预措施来减少个人肉类消费，通常是直接吸引个人的健康动机。然而，对营养行为变化的研究表明，将行为与道德价值观、身份形成和现有社会运动联系起来的干预措施可能特别有效且持久。关于肉类消费，初步证据和心理学理论表明，与动物福利相关的呼吁可能具有有效利用人类心理这些要素的巨大潜力。我们的目标是进行系统回顾和定量荟萃分析，评估动物福利相关呼吁对实际或预期肉类消费或购买的有效性。我们的研究将批判性地综合有关干预个体肉类消费的心理机制的当前知识状况，并根据经验确定最有效的基于动物福利的干预措施背后的心理特征。方法系统检索8个学术数据库，广泛检索未发表的灰色文献。我们将纳入旨在通过提及或描绘动物福利来评估旨在减少肉类消费或购买的干预措施的研究，这些研究衡量与肉类消费或购买相关的结果，并且具有控制条件。合格的研究可以从任何人群中招募，以任何语言撰写，并可以随时发表或发布。我们将对这些研究进行荟萃分析，报告汇总点估计和描述潜在异质效应分布的其他指标。我们将评估研究的偏倚风险并对发表偏倚进行敏感性分析。我们描述了可能的后续分析，以调查干预效果的假设调节因素。讨论拟议的系统评价和荟萃分析的结果，包括现有文献中任何已确定的方法学局限性，可以为成功的循证干预措施的设计提供信息，这些干预措施具有改善人类、动物和环境福祉的广泛潜力。系统审查注册 该协议通过开放科学框架 (https://osf.io/d3y56/registrations) 进行预注册。