An irritable bowel syndrome-specific symptom questionnaire: development and validation.

Area of Science:

• Gastroenterology
• Psychometrics
• Health Outcomes Research

Background:

• No validated self-assessment tools exist for irritable bowel syndrome (IBS) symptom evaluation.
• Development of a disease-specific instrument is crucial for accurate IBS symptom assessment.

Purpose of the Study:

• To develop and validate a disease-specific symptom questionnaire for patients with IBS.
• To create a reliable and user-friendly instrument for assessing IBS symptom severity.

Main Methods:

• Psychometric evaluation of 234 IBS patients using the modified Gastrointestinal Symptom Rating Scale (GSRS-IBS).
• Validation against disease-specific health-related quality of life (HRQL) questionnaires.
• Item reduction based on ceiling effects, construct relevance, and inter-item correlations, followed by confirmatory factor analysis.

Main Results:

• The final 13-item GSRS-IBS questionnaire covers satiety, pain, diarrhea, constipation, and bloating.
• High internal consistency reliability (0.74-0.85) and confirmed construct validity were observed.
• Abdominal pain, bloating, and diarrhea were identified as the primary symptom clusters impacting HRQL.

Conclusions:

• The GSRS-IBS is a concise and practical instrument for IBS symptom assessment.
• The questionnaire exhibits excellent psychometric properties, making it suitable for clinical and research use.