The Effect of Preoperative Abdominal Massage on The Development of Postoperative Constipation: A Randomised Controlled Study

Abdominal massage, being a low-cost, non-invasive procedure with no known harmful side effects, and one that nurses can integrate into clinical practice, plays an important role in the management of constipation.

This study is a single-center, randomized controlled experimental trial planned to be conducted in the General Surgery Department of a Training and Research Hospital in Istanbul. Standard operating procedures for patient recruitment, data collection, data management, adverse event reporting, and change management processes have been predefined. The experimental group will receive abdominal massage twice daily for 15 minutes, while the control group will continue with routine care. Adverse events will be recorded after each session, and necessary protocol changes will be documented in accordance with formal change management procedures. The sample size was determined based on a power analysis performed with G*Power 3.1; 30 participants were planned for each group (total n=60; α=0.05, power=0.80). A complete case analysis approach will be adopted for missing data resulting from data inconsistencies, out-of-range results, or unanswered items, and group assignments will continue until data is complete. In accordance with the statistical analysis plan, the Mann-Whitney U test will be used for between-group comparisons and the Wilcoxon test for within-group comparisons for the Bristol Stool Scale (BSS) score, which is the primary outcome measure; For the secondary outcome measure, stool type distribution, the Chi-square test will be applied. Effect size will be reported using Cohen's d and odds ratio, and the statistical significance threshold will be set at p<0.05.