Setting. The study will be conducted in the Endoscopy Unit of the Department of Gastroenterology, Gazi University Faculty of Medicine.
Participants and allocation. Adults aged 18 years or older scheduled for elective ERCP who are able to read and understand Turkish and who provide written informed consent will be enrolled. Participants will be randomly allocated in a 1:1 ratio to the intervention or control group using a computer-generated randomization sequence with sequentially numbered, opaque, sealed envelopes for allocation concealment.
Control group. Patients will receive the routine information ordinarily provided in the unit before ERCP, consisting of the standard verbal explanation given during the informed consent process.
Intervention group. In addition to routine information, patients will receive a structured, one-to-one educational session delivered by a trained nurse. The session lasts approximately 30 to 45 minutes and comprises a standardized slide presentation and a printed colour brochure covering the purpose of ERCP, the sequence of events on the procedure day, sedation, expected sensations, duration, the recovery period, postprocedural instructions and warning symptoms.
Assessments. A structured interview form will record demographic and clinical characteristics. The state subscale of the Spielberger State-Trait Anxiety Inventory and a 17-item multiple-choice knowledge questionnaire will be administered at baseline (before allocation) and immediately before the procedure, after the intervention has been delivered and before any sedative agent is given. A further state anxiety assessment will be performed two hours after the end of the procedure.
Blinding. Because of the nature of the intervention, participants and the nurse delivering the education cannot be blinded. The investigator performing data entry and statistical analysis will be blinded to group allocation.
Statistical analysis. Data will be analysed with SPSS version 26.0. Distribution will be assessed using the Kolmogorov-Smirnov test. Between-group comparisons of continuous variables will use the independent samples t test or the Mann-Whitney U test as appropriate, and within-group comparisons will use the paired t test or the Wilcoxon signed rank test. Categorical variables will be compared using the chi-square test or Fisher exact test. Analysis of covariance will be used to compare postintervention scores with adjustment for baseline values. A two-sided p value below 0.05 will be considered statistically significant.