Closing the dietary fibre gap - developing a novel dietary fibre screening tool (SCREEN-IT) for the UK population: validity, reproducibility and usability insights

Abstract

Insufficient dietary fibre intake can increase chronic disease risk with identification of effective strategies considered a public health priority. However, there are no UK-based dietary fibre intake tools to estimate consumption habits. This study addresses this gap by developing a novel dietary fibre screening tool (SCREEN-IT) for the UK population and explores validity, reproducibility and usability insights. SCREEN-IT was developed based on key dietary fibre-rich food categories in the UK diet. The validity of SCREEN-IT (10-item) was tested against a UK-based Food Frequency Questionnaire (eNutri-FFQ; 157-item) seven-days apart (n = 70; 55.1 ± 18.7 years). SCREEN-IT reproducibility (n = 155; 51.7 ± 18.2 years) was evaluated on two occasions (four-weeks apart) and usability (System Usability Scale; SUS) was assessed. Intra-class correlation coefficients, percentage difference, quartile agreement, weighted kappa and Bland-Altman plots were used to quantify agreement and extent of bias. Agreement between methods (SCREEN-IT vs. eNutri-FFQ) was “acceptable to good agreement”; higher dietary fibre estimates from eNutri-FFQ (mean bias: −3.91 g/d). SCREEN-IT was quick to complete (< 5-min) with higher SUS than eNutri-FFQ (83.4 vs. 76.8/100). SCREEN-IT was reproducible on re-test (“acceptable to good agreement”), mean bias close to zero (−0.04 g/d), high usability (84.9/100) and received positive feedback (easy-to-use, functional, thought-provoking, enjoyable). SCREEN-IT was successfully developed with favourable validity, reproducibility and usability feedback. It was considered a suitable tool to estimate dietary fibre intake for the UK population. This novel tool could help raise dietary fibre awareness by promoting relevant food sources in a quick and easy way to increase future intake.