This prospective observational cohort study aims to examine changes in occupational disidentification among undergraduate nursing interns during clinical internship and to identify factors associated with high-risk trajectories. Undergraduate nursing students will be followed using online questionnaires from the end of the first internship week and approximately every three months until the end of internship. The study will assess occupational disidentification, personal psychological resources, clinical learning environment, occupational stigma, negative clinical experiences, transition shock, emotional exhaustion, occupational fatigue, sleep, and musculoskeletal symptoms.

Inclusion Criteria:

1. Full-time undergraduate students majoring in nursing.
2. Students who are about to enter clinical internship or are in the early stage of clinical internship.
3. Students who are able to use the WeChat mini-program to complete questionnaires.
4. Students with normal reading comprehension ability.
5. Students who voluntarily agree to participate in the study and provide informed consent.

Exclusion Criteria:

1. Students who are unable to complete the internship during the study period due to suspension of schooling, withdrawal from school, military service, long-term sick leave, or other reasons.
2. Students who have participated in similar interventional studies that may affect the assessment of the primary outcome.
3. Students with severe physical or mental illness, or other conditions that make them unable to complete the questionnaires independently.

Exclusion From Analysis Criteria:

1. Questionnaires with an obviously too short completion time, below the minimum reasonable response time set by the research team.
2. Questionnaires with patterned responses or obvious logical inconsistencies.
3. Questionnaires with missing key variables that cannot be used for the main statistical analysis.
4. Repeated submissions at the same time point where the valid version cannot be confirmed.

The study population will consist of full-time undergraduate nursing students from multiple participating universities in China, including students who are about to enter or are in the early stage of clinical internship. Eligible students will be recruited using a non-probability convenience sampling method and followed prospectively through online questionnaires during the internship period.

Individual participant data will not be shared because the study involves sensitive questionnaire data from undergraduate nursing interns and data sharing is restricted by ethics approval and participant consent.