Ethics education is widely expected to improve clinicians’ capacity to recognise, analyse, and respond to ethically difficult situations, yet educational success is often inferred from proximal outcomes such as knowledge, moral sensitivity, reasoning scores, or learner perceptions. Whether such changes alter professional behaviour, transfer into clinical decision-making, or persist within practice remains less certain. This systematic review examined ethics education across four prespecified domains: moral reasoning; reflection and ethical sensitivity; behaviour and workplace performance; and clinical transfer and sustainability. The review used PRISMA 2020 reporting principles and predefined eligibility, extraction, risk-of-bias, outcome-classification, and synthesis procedures. Health-professions students and practicing professionals were eligible when an identifiable ethics-focused educational intervention assessed at least one prespecified outcome domain. Educational, simulation, clinical-placement, and workplace interventions were considered. Evidence was synthesized narratively because intervention designs, professions, outcome measures, and follow-up periods were not sufficiently uniform to justify assuming a common effect metric. Educational outcomes were explicitly distinguished from enacted workplace behaviour and sustained transfer. The evidence showed the clearest and most frequent signals at proximal educational levels, particularly ethical reasoning, reflection, moral sensitivity, and related learner outcomes. Findings were nevertheless heterogeneous, and some interventions produced little or no measurable change on formal competence measures. Behavioural evidence was less common and varied in its proximity to real practice. The strongest transfer-relevant studies embedded ethics support within clinical work or evaluated actual professional decision processes. Evidence for sustained practice change remained comparatively limited and context dependent. Ethics education can change ethically relevant learning outcomes, but the literature does not support treating such change as equivalent to altered clinical practice. The principal review finding is therefore a distinction in evidential directness: proximal educational improvement, enacted professional behaviour, clinical transfer, and sustained practice effects require separate demonstration. Stronger longitudinal, workplace-based, and implementation-sensitive research is needed before durable clinical impact can be inferred.
