BACKGROUND:The increased availability of computers and the efficiency and user-acceptability of computer-assisted questioning have increased the attractiveness of computer-administered querying for large-scale population nutrition research during the last decade. The Young Adolescents' Nutrition Assessment on Computer (YANA-C), a computer-based 24-h dietary recall, was originally developed to collect dietary data among Belgian-Flemish adolescents. A web-based version was created to collect parentally reported dietary data of preschoolers, called Young Children's Nutrition Assessment on the Web (YCNA-W), which has been improved and adapted for use in young adolescents: Children and Adolescents' Nutrition Assessment and Advice on the Web (CANAA-W). The present study describes recent developments and the formative evaluation of the dietary assessment component. METHODS:A feasibility questionnaire was completed by 131 children [mean (SD) age: 11.3 (0.7) years] and 53 parents. Eight focus groups were held with children (n = 65) and three with parents (n = 17). RESULTS:Children (C) and parents (P) found the instrument clear (C: 97%; P: 94%), comprehensible (C: 92%; P: 100%), attractive (C: 84%; P: 85%), fun (C: 93%; P: 83%) and easy to complete (C: 91%; P: 83%). There was ample explanation (C: 95%; P: 94%); the pictures were clear (C: 97%; P: 96%); and most respondents found the food items easy to find (C: 71%, P: 85%). The results helped to refine the lay out and structure of the instrument and the list of food items included. CONCLUSIONS:Children and parents were enthusiastic. The major challenge will be to convince parents who are less interested in dietary intake and less computer literate to participate in this type of study. Children in this age group (11-12 years) should complete the instrument with assistance from an adult.