Reliability and validity of the Bowel Function Index for evaluating opioid-induced constipation: translation, cultural adaptation and validation of the Portuguese version (BFI-P)

• Type: Article in International Scientific Journal
• Date: 2017

Authors

Duenas, M (Author) Other; Mendonca, L (Author) Other; Sampaio, R (Author) FMUP; Gouvinhas, C (Author) Other; Oliveira, D (Author) Other; Castro-Lopes J.M. (Author) FMUP; Azevedo L (Author) FMUP

Journal

Title: Current Medical Research and Opinion

Vol. 33

Pages: 563-572

ISSN: 0300-7995

Publisher: Taylor & Francis

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-00M-K4K

DOI: 10.1080/03007995.2016.1273204

Abstract (EN): Objective: The Bowel Function Index (BFI) is a simple and sound bowel function and opioid-induced constipation (OIC) screening tool. We aimed to develop the translation and cultural adaptation of this measure (BFI-P) and to assess its reliability and validity for the Portuguese language and a chronic pain population. Methods: The BFI-P was created after a process including translation, back translation and cultural adaptation. Participants (n=226) were recruited in a chronic pain clinic and were assessed at baseline and after one week. Internal consistency, test-retest reliability, responsiveness, construct (convergent and known groups) and factorial validity were assessed. Results: Test-retest reliability had an intra-class correlation of 0.605 for BFI mean score. Internal consistency of BFI had Cronbach's alpha of 0.865. The construct validity of BFI-P was shown to be excellent and the exploratory factor analysis confirmed its unidimensional structure. The responsiveness of BFI-P was excellent, with a suggested 17-19 point and 8-12 point change in score constituting a clinically relevant change in constipation for patients with and without previous constipation, respectively. Conclusions: This study had some limitations, namely, the criterion validity of BFI-P was not directly assessed; and the absence of a direct criterion for OIC precluded the assessment of the criterion based responsiveness of BFI-P. Nevertheless, BFI may importantly contribute to better OIC screening and its Portuguese version (BFI-P) has been shown to have excellent reliability, internal consistency, validity and responsiveness. Further suggestions regarding statistically and clinically important change cut-offs for this instrument are presented.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10