Investigating aspects of social acceptance of Rapid Autopsy Program (RAP) in Japan: an exploratory survey

Abstract Background Rapid Autopsy Program (RAP) provides postmortem tissue specimens for biomedical research, including molecular oncology and personalized medicine. However, public perspectives on RAP and related forms of postmortem human tissue use remain insufficiently characterized in Japan, where cultural and emotional sensitivities surrounding deceased bodies may be relevant to attitudes toward such practices. This study examined self-reported responses to a brief description of an RAP-like postmortem research procedure and compared these responses across several evaluative aspects and related postmortem practices. Methods A nationwide non-probability online cross-sectional survey was conducted in January 2025 with 3,102 Japanese participants, with quotas by sex and age to approximate national population distributions. Participants read brief descriptions of four postmortem practices—pathological autopsy, RAP, systematic dissection, and organ transplantation—and provided self-reported responses to four evaluative items concerning RAP: Perceived Social Necessity, Support for Institutionalization, Personal Use Intention, and Intention to Recommend to Family. Responses across these items and differences by sex and age were examined using a three-way mixed-design ANOVA. Results Across the four evaluative items, RAP was rated significantly higher than systematic dissection but lower than pathological autopsy and organ transplantation. Responses showed a progressive decline from societal-level to personal and familial involvement: perceived social necessity received 80.3% positive responses, whereas positive responses declined to 46.0% for personal use intention and 33.0% for intention to recommend to family. For perceived societal necessity, 46.1% selected “slightly agree,” indicating that a substantial proportion of positive responses reflected low-intensity agreement rather than strong active support. Demographic differences by sex and age were statistically significant, but their practical effect sizes were small compared with the substantially larger effect of the evaluative item factor. Conclusions Under the simplified informational conditions of the survey, the self-reported social acceptance of RAP in Japan is characterized by stronger support for societal-level necessity than for personal or familial willingness, illustrating a clear societal–personal gap. Although statistically significant differences by sex and age were observed, their effect sizes were small relative to this overall pattern. These findings highlight the importance of further examining the factors underlying personal and familial hesitation toward RAP, including the role of family communication and decision-making.