Associations of Knowledge and Skills With Preconception Health Behaviors Based on the Information-Motivation-Behavioral Skills Model: An Integrated Individual and Dyadic Mediation Analysis

Purpose To evaluate the pathways through which preconception health knowledge relates to preconception health behaviors via behavioral skills among Chinese reproductive-aged individuals and couples using the Information–Motivation–Behavioral Skills model, and to assess dyadic partner effects. Design Cross-sectional study with individual-level mediation and dyadic path models. Setting Population-based survey in Zhejiang Province, China (July–September 2023). Sample 1991 individuals (1086 women; 905 men), including 458 heterosexual couples. Measures Preconception health behavior score (0-100) summing >20 guideline-recommended behaviors; preconception health knowledge; behavioral skills; sociodemographics. Analysis Individual-level mediation estimated with Sobel–Goodman tests; dyadic effects estimated using Actor–Partner Interdependence Model extended to Mediation (APIMeM) via path analysis; two-sided tests with P < 0.05. Results Mean behavior scores: women 71.27 ± 9.03; men 71.12 ± 9.96. Women: total effect of knowledge on behaviors 0.896 ( P = 0.001); direct 0.785 ( P = 0.003); indirect via skills 0.111 ( P = 0.033). Men: total 1.731 ( P < 0.001); direct 1.313 ( P < 0.001); indirect 0.418 ( P < 0.001). Dyadic analyses showed partner skill-to-behavior effects: women’s skills → men’s behaviors β = 0.127 ( P = 0.003); men’s skills → women’s behaviors β = 0.153 ( P = 0.001). Conclusion Preconception knowledge and behavioral skills are linked to healthier preconception behaviors, with meaningful partner interdependence. Couple-centered, skill-building interventions may improve preconception health and pregnancy outcomes. Cross-sectional design limits causal inference; self-reported behaviors may introduce bias; findings from one province may limit generalizability.