Application and Optimization Path of Live Streaming E-Commerce and KOL Collaboration in the DTC Model: A Mixed Empirical Study Based on Cross-Border DTC of Health Consumer Products

Abstract

Cross‑border DTC export of dietary supplements faces dilemmas including rising traffic costs, moral hazards in KOL cooperation, and imbalance between short‑term conversion and long‑term brand equity. Existing studies separate the internal correlations among consumer perception, contractual game and brand performance, and lack special mixed empirical tests for health‑related categories. Integrating the S‑O‑R theory and Stackelberg leader‑follower game, this paper constructs a three‑layer analytical framework of “micro‑perception‑meso‑contract‑macro‑performance”. Mixed empirical tests are carried out based on 327 groups of TikTok panel data and 486 valid questionnaires from European and American consumers. The study finds that perceived trust plays a core mediating role; the three‑dimensional mixed contract can realize Pareto improvement and lift KOL’s optimal effort level by 21.7% (Li, X., & Zhang, Y., 2021); combinations such as vertical micro‑KOC matrices form high‑performance configurations, while single investment in top‑tier KOLs generates diseconomies of scale. This research expands the marketing theory for cross‑border DTC and provides quantitative KOL operation and risk‑control schemes for the overseas expansion of health‑related categories.