Bowel Preparation Quality Following Video-Based Intervention and Educational Booklet Versus Standard of Care in an Outpatient Setting

BACKGROUND AND RATIONALE: Non-pharmacological factors, especially the modality of patient education, may influence bowel preparation quality, yet are underexplored and likely context-dependent based on local staffing, patient characteristics, and practice norms. STUDY DESIGN: Prospective, single-endoscopist-blinded, three-arm randomized controlled trial (RCT) with intention-to-treat (ITT) primary analysis. Allocation 1:1:1 using computer-generated random numbers. Endoscopist and endoscopy nurses are blinded to group assignment; participants cannot be blinded due to the nature of the intervention. SETTING: Hospital Sibu Endoscopy Unit, Sarawak, Malaysia. Colonoscopies performed by qualified surgeons or registrars under supervision; all endoscopists undergo refresher training on Boston Bowel Preparation Scale (BBPS) scoring for consistency. STUDY ARMS (INTERVENTIONS): Arm A (Control): Usual care. Physician/nurse-delivered verbal instructions plus standard pharmacy instructions for bowel preparation solution (split-dose PEG 3L). Arm B (Written): Tri-lingual (Malay/English/Chinese), plain-language educational leaflet reviewed by health literacy expert, plus brief verbal explanation. Arm C (Visual): Short, structured instructional videos accessible via smartphone QR code, reviewed by health literacy expert, plus brief verbal explanation. SAMPLE SIZE AND STATISTICAL ANALYSIS: N=324 (108 per arm). Primary analysis: Intent-to-treat chi-square test comparing adequate vs inadequate BBPS across three arms. Pairwise comparisons with Bonferroni adjustment. Multivariable logistic regression adjusts for prespecified covariates (age, sex, BMI, diabetes, education, language, constipation, study arm). PRIMARY OUTCOME: Adequate versus inadequate bowel preparation on Boston Bowel Preparation Scale (BBPS). Adequate = total ≥6 with all segments ≥2. SECONDARY OUTCOMES: Polyp detection rate; cecal intubation and withdrawal times; cancellation and repeat rates; patient tolerance; complications; patient-reported clarity and helpfulness; anxiety (VAS-A); demographic predictors.