Quantitative analysis of China’s selenium-enriched policy texts: Based on a three-dimensional framework of “theme–instrument–effectiveness”

Selenium, as an essential trace element for human health, plays a critical role in antioxidant defense, immune regulation, and disease prevention. With approximately 72% of China's soil area being selenium-deficient, developing the selenium-enriched industry has become a strategic priority for local governments under the "Healthy China" and Rural Revitalization initiatives. While existing research has extensively explored selenium's scientific mechanisms and industrial development pathways, a critical research gap remains in the systematic quantitative evaluation of selenium-enriched policy texts. This study addressed this gap by conducting a comprehensive quantitative analysis of 42 selenium-enriched policy documents issued in China from 2009 to 2025. Employing a three-dimensional analytical framework of "policy theme-policy instrument-policy effectiveness" integrated with Latent Dirichlet Allocation (LDA) topic modeling, content analysis, and the Policy Modeling Consistency (PMC) index model, this study reveals three key findings: (1) Current policies heavily emphasize industrial cultivation and brand building while paying insufficient attention to long-term selenium resource management and cross-regional coordination; (2) Policy instruments predominantly rely on supply-side inputs and indirect market cultivation, with weak direct stimulation of consumer health demand; (3) While policy design demonstrates good operationality (average PMC index = 6.9), it exhibits deficiencies in long-term strategic planning and national-level top-level design. This study provides actionable insights for policymakers to strengthen national top-level design, balance short-term industrial growth with long-term resilience construction, and optimize policy tool configurations to stimulate endogenous market vitality for the high-quality development of the selenium-enriched industry.