Web-based tools have the potential to reduce the cost of dietary assessment; however, it is necessary to establish their performance compared to traditional dietary assessment methods. This study aims to compare nutrient and food intakes derived from Foodbook24 to those obtained from an interview-led 24-h dietary recall (24HDR). Seventy-nine adult participants completed one self-administered 24HDR using Foodbook24 and one interviewer-led 24HDR on the same day. Following a 10 days wash-out period the same process was completed again in opposite order to the previous study visit. Statistical analysis including Spearman's rank order correlation, Mann-Whitney U tests, cross-classification analysis, and "Match", "Omission", and "Intrusion" rates were used to investigate the relationship between both methods. Strong, positive correlations of nutrient intake estimated using both methods was observed (rs = 0.6-1.0; p < 0.001). The percentage of participants classified into the same tertile of nutrient intake distribution using both methods ranged from 58% (energy) to 82% (vitamin D). The overall match rate for food intake between both methods was 85%, while rates for omissions and intrusions were 11.5% and 3.5%, respectively. These results, alongside the reduced cost and participant burden associated with Foodbook24, highlight the tool's potential as a viable alternative to the interviewer-led 24HDR.
Keywords: 24 h dietary recall; Foodbook24; comparison; dietary assessment; interviewer led; self-administered; web-based.