Are Digital Influence Models Portable? A Transnational MICOM Test of the SOR Framework in Andean Organic Consumption

Comparative research on digital social influence and sustainable food consumption has grown substantially; however, most transnational studies do not verify measurement invariance nor assess whether observed structural differences reflect genuine cultural variation or measurement artifacts. This study addresses this gap by applying the Stimulus–Organism–Response (SOR) model to examine whether Social Media Content (SMC) and Online Member Group Support (OMGS) influence Organic Product Purchasing Behavior (OPPB) through Environmental Attitude (EA) and Subjective Norms (SN) in Ecuador, Chile, and Peru. A cross-sectional quantitative design was implemented with 809 organic consumers, analyzed using PLS-SEM in two stages: assessment of compositional invariance via the MICOM procedure and multigroup analysis (MGA) based on permutations. Full compositional invariance was confirmed across the three national groups, validating transnational structural comparability. The SOR model held consistently, with EA emerging as a stable predictor of OPPB. Significant structural differences were identified: the SMC→SN path was significantly stronger in Chile (β = .671 vs. β = .558 in Peru; p <.01), whereas the OMGS→EA path was stronger in Peru (β = .284 vs. β = .211 in Chile; p < .05). These findings underscore the need to formally verify invariance before drawing transnational conclusions and highlight the cultural contingency of sustainable digital marketing strategies in Andean emerging markets.