Objective To evaluate, using an online non-probability sample, the beliefs about and attitudes towards cancer prevention of people professing vaccination scepticism or conspiracy theories. Design Cross sectional survey. Setting Data collected mainly from ForoCoches (a well known Spanish forum) and other platforms, including Reddit (English), 4Chan (English), HispaChan (Spanish), and a Spanish language website for cancer prevention (mejorsincancer.org) from January to March 2022. Participants Among 1494 responders, 209 were unvaccinated against covid-19, 112 preferred alternative rather than conventional medicine, and 62 reported flat earth or reptilian beliefs. Main outcome measures Cancer beliefs assessed using the Cancer Awareness Measure (CAM) and Cancer Awareness Measure Mythical Causes Scale (CAM-MYCS) (both validated tools). Results Awareness of the actual causes of cancer was greater (median CAM score 63.6%) than that of mythical causes (41.7%). The most endorsed mythical causes of cancer were eating food containing additives or sweeteners, feeling stressed, and eating genetically modified food. Awareness of the actual and mythical causes of cancer among the unvaccinated, alternative medicine, and conspiracy groups was lower than among their counterparts. A median of 54.5% of the actual causes was accurately identified among each of the unvaccinated, alternative medicine, and conspiracy groups, and a median of 63.6% was identified in each of the three corresponding counterparts (P=0.13, 0.04, and 0.003, respectively). For mythical causes, medians of 25.0%, 16.7%, and 16.7% were accurately identified in the unvaccinated, alternative medicine, and conspiracy groups, respectively; a median of 41.7% was identified in each of the three corresponding counterparts (P<0.001 in adjusted models for all comparisons). In total, 673 (45.0%) participants agreed with the statement “It seems like everything causes cancer.” No significant differences were observed among the unvaccinated (44.0%), conspiracist (41.9%), or alternative medicine groups (35.7%), compared with their counterparts (45.2%, 45.7%, and 45.8%, respectively). Conclusions Almost half of the participants agreed that “It seems like everything causes cancer,” which highlights the difficulty that society encounters in differentiating actual and mythical causes owing to mass information. People who believed in conspiracies, rejected the covid-19 vaccine, or preferred alternative medicine were more likely to endorse the mythical causes of cancer than their counterparts but were less likely to endorse the actual causes of cancer. These results suggest a direct connection between digital misinformation and consequent erroneous health decisions, which may represent a further preventable fraction of cancer. Data are available from the corresponding author (lcostas@iconcologia.net) on reasonable request.

中文翻译：

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一切都会致癌？反疫苗者、地平论者和爬行动物阴谋论者对癌症预防的信念和态度：在线横断面调查


目的 使用在线非概率样本评估对疫苗接种持怀疑态度或阴谋论的人们对癌症预防的信念和态度。设计横断面调查。设置 1月至3月主要从ForoCoches（知名西班牙语论坛）和其他平台收集数据，包括Reddit（英语）、4Chan（英语）、HispaChan（西班牙语）以及西班牙语癌症预防网站（mejorsincancer.org） 2022 年。参与者 在 1494 名响应者中，209 人未接种 covid-19 疫苗，112 人更喜欢替代医学而不是传统医学，62 人报告说地球是平的或爬行动物信仰。主要结果衡量使用癌症意识测量（CAM）和癌症意识测量神秘原因量表（CAM-MYCS）（均为经过验证的工具）评估的癌症信念。结果 对癌症实际原因的认识（CAM 中位数 63.6%）高于对神话原因（41.7%）的认识。最受认可的神秘癌症原因是食用含有添加剂或甜味剂的食物、感到压力以及食用转基因食品。未接种疫苗、替代医学和阴谋群体对癌症的实际和神话原因的认识低于同行。在未接种疫苗组、替代医学组和阴谋组中，准确识别出实际原因的中位数为 54.5%，在三个相应对应组中，准确识别出的实际原因中位数为 63.6%（P=0.13、0.04 和 0.003，分别）。对于神秘原因，在未接种疫苗组、替代医学组和阴谋组中准确识别的中位数分别为 25.0%、16.7% 和 16.7%；中位数为 41。三个相应对应物中的每一个都识别出 7%（所有比较的调整模型中的 P<0.001）。总共有 673 名（45.0%）参与者同意“似乎一切都会导致癌症”的说法。与对应群体（分别为 45.2%、45.7% 和 45.8%）相比，未接种疫苗组（44.0%）、阴谋论者组（41.9%）或替代医学组（35.7%）没有观察到显着差异。结论 几乎一半的参与者同意“似乎一切都会导致癌症”，这突显了社会因海量信息而难以区分实际原因和神话原因。相信阴谋论、拒绝 covid-19 疫苗或偏爱替代医学的人比其他人更有可能认可癌症的神秘原因，但不太可能认可癌症的实际原因。这些结果表明数字错误信息与随之而来的错误健康决策之间存在直接联系，这可能代表了进一步可预防的癌症部分。数据可根据合理要求从通讯作者 (lcostas@iconologia.net) 处获取。