Relative validity of a non-quantitative 33-item dietary screener with a semi-quantitative food frequency questionnaire among young adults
Lorentz Salvesen, Andrew K. Wills, Nina Cecilie Øverby, Dagrun Engeset, Anine Christine Medin
Abstract
Abstract The objective of the study was to assess the concordance and ranking ability of a non-quantitative 33-item dietary screener developed to assess the diet of young adults in Norway, ‘MyFoodMonth 1.1’, compared to a semi-quantitative food frequency questionnaire (FFQ). Data were collected in a cross-sectional dietary survey evaluating the diets of students at the University of Agder, in southern Norway. The students were asked to complete both a dietary screener and an FFQ. Data collection was carried out from September to December 2020. Participants were first-year university students aged ≥18 years familiar with Scandinavian language. Almost half of the eligible sample ( n 344) was excluded due to not completing the FFQ, compared to 1⋅7 % not completing the dietary screener, resulting in 172 (66 % female) participants with a median age of 21 years. For most items of the dietary screener ( n 27/33, 82 %), all aspects of diet quality and components of the Diet Quality Score showed moderate-to-strong concordance with the FFQ evaluated using Kendall's tau-b analyses ( t > 0⋅31), supported by visual inspection of box and whisker plots and descriptive ranking ability in a cross-tabulation. There was little evidence to suggest that concordance was dependent on sex. The concordance and ranking ability of ‘MyFoodMonth 1.1’ is considered satisfactory compared to a semi-quantitative FFQ. This rapid dietary assessment instrument presents a valuable addition to traditional instruments and a possible solution to recruit hard-to-reach parts of the population.