Neurogenic bowel dysfunction score in spinal cord-injured patients: translation and validation of the Dutch-language NBD score

Study design: This is a prospective validation study. Objectives: The neurogenic bowel dysfunction (NBD) score is a widely used symptom-based questionnaire evaluating bowel dysfunction and its impact on quality of life (QoL) in spinal cord-injured patients. This study aimed to translate and validate a Dutch-language NBD score in patients with SCI. Setting: Patients with SCI visiting the urology department or general practitioner (GP) in Rotterdam, the Netherlands. Methods: Standardized guidelines were followed for the translation and validation process of the NBD score. Adult patients with SCI visiting our urology department were asked to participate by filling in a set of questionnaires: the NBD score, the Fecal Incontinence Quality of Life scale (FIQL), the Fecal Incontinence Severity Index (FISI), and the European Quality of life 5-Dimension 3-Level questionnaire (EQ-5D-3L) at baseline and 1–2 weeks afterward. A control group recruited at a GP office completed the questionnaires once. The following measurement properties were evaluated: content validity, internal consistency, reproducibility, criterion-, and construct validity. Results: Fifty-eight patients and 50 references were included. Content validity was adequate, internal consistency was moderate (Cronbach’s alpha 0.56 and 0.30) and reproducibility was adequate (ICC 0.87). Criterion validity was confirmed; NBD score correlated significantly with the FIQL, FISI, and EQ-5D-3L. NBD scores in the patient group were significantly higher than in references, demonstrating good construct validity. Conclusions: The Dutch-language version of the NBD score showed moderate to good measurement properties, and therefore is a reliable tool to measure bowel dysfunction in patients with SCI. We recommend standardized usage of this questionnaire for clinical evaluation and research purposes.