Development and validation of a quantitative food frequency questionnaire to assess free sugar intake among Sri Lankan preschool children

Abstract Background: Monitoring the free sugar intake of preschool children is important for population health surveillance and evaluation of community-wide efforts at non-communicable diseases and dental caries prevention. Appropriate dietary assessments tools are also needed to underpin clinical prevention for patients. Thus, anappropriate dietary assessment tool applicable for large-scale, community-based studies without an excessive participant burden is needed, such as a quantitativefood frequency questionnaire that assesses dietary data retrospectively. Suchtools also need to be tailored and validated for the cultural context andpopulation concerned. Sri Lanka is currently lacking such a tool for use amongits pre-school population.Methods: In the development phase, a sample of 518 pre-school children and their caregivers were selected from pre-schools in the District of Colombo, Sri Lanka. Three 24-hour dietary recalls were collected from each child and based on that, a 67-item food frequency questionnaire was developed, including commonly consumed free sugar-containing food items. In the validation phase, 108 pairs of preschool children aged 04-05-years, and their caregivers participated. The relative validity of the food frequency questionnaire was assessed by comparing it with three, 24-hour dietary recalls. The test-retest reliability was assessed by repeated application of the food frequency questionnaire to the same population in six weeks intervals.Results: The free sugar intake values calculated from the food frequency questionnaire when compared with three, 24-hour dietary recalls indicated a good correlation, good agreement in cross classifying participants to tertiles based on their sugar intake levels and a good agreement in bland and Altman graphs at different food group levels and total free lsugar intake. The food frequency questionnaire measured sugar intake levels slightly higher than three 24-hour dietary recalls. Similarly, the free sugar intake values calculated by repeated application of the food frequency questionnaire also showed a good agreement at the group and individual levels as well as a good correlation.Conclusion: The newly developed quantitative food frequency questionnaire was found as a valid and reliable instrument to assess the free sugar intake among preschool children quantitatively as a total or by different food and beverage group levels.