Uneven effects of accreditation on medical students’ learning outcomes: A quasi-experimental study across learning domains and institutional contexts

Accreditation is widely used to ensure quality in medical education; however, its effects on student learning outcomes across various domains and institutional contexts remains unclear. This study examines whether and how accreditation influences value-added learning outcomes among Chinese medical students. Using a quasi-experimental design, we analyzed data from the 2019 to 2020 China Medical Student Survey (CMSS), which was linked to national accreditation records. Final-year students from institutions accredited between the two survey waves were classified as the treatment group; those from non-accredited institutions served as controls. Value-added learning outcomes were measured as self-assessed growth across four domains: science and scholarship, clinical practice, health and society, and professionalism. Propensity score matching and difference-in-differences (PSM-DID) estimation were applied. Guided by goal-setting theory, we interpret heterogeneity in accreditation effects across learning domains and institutional contexts. Accreditation significantly improved learning outcomes in clinical practice (β = 0.275, p = 0.049), but had no significant effects in other domains. Subgroup analyses revealed stronger effects in non-elite universities and medical schools embedded within comprehensive universities, whereas limited or negative effects were observed in elite universities and free-standing medical colleges. The effects of accreditation varies unevenly across different learning domains and institutional contexts. Guided by goal-setting theory, our findings suggest that institutional response depends on the perceived difficulty, observability, and relevance of accreditation goals.