This study aims to develop and validate a disease-specific self-care measurement scale for patients with Inflammatory Bowel Disease (IBD). The research follows a sequential mixed-methods design: a qualitative phase to identify key self-care concepts, followed by a quantitative phase to test the psychometric properties of the newly developed SC-IBD scale in an outpatient population.

This study is designed to develop and validate the SC-IBD scale, a disease-specific instrument for measuring self-care in patients with Inflammatory Bowel Disease (IBD). The project uses a sequential exploratory mixed-methods design.

In the qualitative phase, semi-structured interviews will be conducted with outpatients diagnosed with IBD to explore their experiences of self-care across the three theoretical dimensions described in the Middle-Range Theory of Self-Care of Chronic Illness: maintenance, monitoring, and management. The qualitative findings will inform item generation and content validity assessment through a multidisciplinary expert panel.

The quantitative phase will include the administration of the preliminary SC-IBD scale to an outpatient cohort in order to evaluate its psychometric properties, including construct validity, internal consistency, and test-retest reliability. Additional validated instruments (DASS-21, SF-12, BIPQ, IBD-Control, and the Short Food Literacy Questionnaire) will be used to assess convergent and divergent validity and to describe relevant psychological, clinical and behavioral correlates of self-care in IBD.

The ultimate goal of the study is to produce a reliable, valid, and clinically useful tool for assessing self-care behaviors in individuals living with IBD, supporting both research and clinical practice.

Inclusion Criteria:

• Voluntary willingness to participate in the study.
• Diagnosis of Inflammatory Bowel Disease (Crohn's Disease or Ulcerative Colitis) for at least 12 months.
• Follow-up in outpatient setting.
• Age 18 years or older.
• Ability to read and speak Italian.
• Ability to understand the study procedures.
• Signed informed consent.

Exclusion Criteria:

• Age younger than 18 years.
• Significant cognitive impairment (e.g., dementia) that may limit participation.
• Insufficient comprehension of the Italian language.
• Severe psychiatric disorders that may compromise participation.
• Severe clinical conditions preventing participation in interviews or questionnaire completion.
• Refusal to sign the informed consent form.

The study population consists of adult outpatients diagnosed with Inflammatory Bowel Disease (Crohn's Disease or Ulcerative Colitis) followed at the IBD outpatient clinic of the Fondazione Policlinico Universitario A. Gemelli IRCCS and affiliated satellite centers. Participants must have received an IBD diagnosis for at least 12 months, be able to read and speak Italian, and be willing to participate in either the qualitative or quantitative phase of the study. A total of 275 patients will be enrolled.

No, there is no plan to share individual participant data (IPD). Data will remain stored in pseudonymized form within the institution according to GDPR and local ethical requirements.