Objective Structured Clinical Examinations (OSCEs) are widely used in nursing education to assess clinical skills but are known to induce significant psychological and physiological stress due to performance anxiety, time pressure, and observation. Exam-related stress has been associated with changes in heart rate variability (HRV), particularly increased low-frequency/high-frequency (LF/HF) ratios, reflecting heightened sympathetic activity. Such stress may negatively affect cognitive performance, clinical competence, and professional readiness.

Nature-based virtual reality (VR) has emerged as a promising intervention for stress reduction by providing immersive, calming environments that promote relaxation and autonomic regulation. Previous studies suggest that short VR-based nature sessions can effectively reduce anxiety and may be more effective than two-dimensional (2D) nature videos, which represent a more accessible but less immersive alternative. However, evidence regarding the use of VR and 2D nature videos for managing stress during high-stakes clinical examinations such as OSCEs is limited.

This randomized controlled study aims to compare the effectiveness of nature-based VR and 2D nature videos in reducing OSCE-related stress among third-year nursing students using physiological (PPG-derived LF/HF ratio) and subjective (STAI and SUD) outcome measures.

Inclusion Criteria:

• Undergraduate third-year nursing students scheduled to take the final OSCE examination.
• Aged between 18 and 25 years.
• Considered healthy, with no known cardiovascular disease or chronic stress-related disorders.
• Willing to participate in the virtual reality or 2D nature video intervention.
• Able to understand the study procedures and provide written informed consent.

Exclusion Criteria:

• Known sensitivity or intolerance to virtual reality, including symptoms such as dizziness, nausea, headache, or visual discomfort.
• Medical conditions that may affect photoplethysmography (PPG) measurements, such as cardiac arrhythmias or significant skin sensitivity at the measurement site.
• Use of medications that may influence heart rate variability, including beta-blockers.
• Inability to allocate sufficient time to participate in the pre-examination stress management intervention.
• Pregnancy, acute illness, or current use of psychiatric medications.
• Refusal to participate or failure to provide informed consent.

Individual participant data (IPD) will not be publicly shared due to privacy concerns and the sensitive nature of maternal and infant health information. However, anonymized data may be made available upon reasonable request to the corresponding author after publication of the study results.