To develop and validate a web-based self-diagnostic questionnaire on school food service offer aimed at food service managers (FSM) by: (i) identifying relevant indicators of school food offer, developing a questionnaire and validating the concept using an expert panel; (ii) validating the questions by comparing the FSM’s responses with observations by dietitians and (iii) undergoing a qualitative evaluation of the tool through direct observation and short interviews.

Mixed methods.

Quebec, Canada.

Nine experts validated the theoretical constructs and indicators on which the questionnaire was based. Inter-rater reliability tests were conducted with thirty-nine FSM, who then participated in interviews about platform functionality satisfaction. Twenty school stakeholders participated in the survey pertaining to their use of the personalised report.

The questionnaire focused on the main school food service’s lunchtime offer and comprised twenty-six questions. The overall strength of agreement was good, and all questions’ strengths of agreement were fair to excellent except for one question. Qualitative data reached saturation and showed that navigation through the questionnaire was fluid. Improvements were suggested to increase user-friendliness and simplicity of both the platform and questionnaire. Results from the survey showed that all respondents were either satisfied or very satisfied with their personalised report.

We successfully developed and validated a web-based self-diagnostic questionnaire. The final version facilitates knowledge mobilisation with school stakeholders and offers a new opportunity for the assessment and surveillance of school food offer.

To estimate reporting bias of WebCAAFE, a web-based questionnaire for the assessment of food intake (recall of frequency of intake of thirty-two food items the day before) and physical activity in schoolchildren.

Cross-sectional study. Self-reported food intake on WebCAAFE was compared with direct observation of school meals in five public schools. Additional data included school grade, sex, BMI, socio-economic status and access to Internet at home. Poisson regression was used to calculate the reporting bias (WebCAAFE v. direct observation) and the sample size necessary to detect a statistically significant difference between WebCAAFE reports and at least 75 % compliance with the recommendations for a healthy diet.

Intentional sample of five elementary public schools in Florianopolis, Brazil.

Schoolchildren (n 629) from 2nd to 5th grades.

Moderate bias magnitude was found for most food groups of interest. Frequency of consumption was not related to the bias. Sample sizes necessary to detect the compliance with dietary recommendations varied between four and seventy-four individuals for the different groups investigated.

After adjusting for moderate bias, WebCAAFE may be used as a food questionnaire for evaluation of schoolchildren’s food compliance on a group level, even with a relatively small sample size.

To assess the feasibility of combining short-term and long-term dietary assessment instruments as new concept for improving usual dietary intake assessment on the individual level.

Feasibility study of completing three 24 h dietary recalls (24-HDR) and a self-administered food propensity questionnaire (FPQ). The 24-HDR was conducted by monthly telephone interviews, using EPIC-SOFT software. The FPQ was completely standardized across cohorts and offered either as a web-based tool or in paper format.

Random sample derived from five ongoing European cohort studies (EPIC-San Sebastian, EPIC-Florence, EPIC-Potsdam, Estonia Genome Center (EGC) and Norwegian Women and Cancer study (NOWAC)).

A total of 400 participants.

Overall, the total participation rate for the present study was 65·3 % (n 261). On average, completion of the 24-HDR was highest for the first 24-HDR (63·0 %) and decreased slightly for the second (60·3 %) and third 24-HDR (56·3 %). The proportions of selecting the web-based FPQ varied among the study centres, with the highest in EGC (92·9 %) and NOWAC (70·0 %) and the lowest in EPIC-San Sebastian (25·5 %) and EPIC-Potsdam (33·9 %). Web users rarely requested support and were younger and more highly educated than those who completed the paper format.

The present study supports the feasibility of a combined application of three 24-HDR and an FPQ in culturally different populations. The varying acceptance of the web-based instrument across populations requires a flexible application of assessment instruments.